"end of aids?" series takes us to new york state, home to nearly one in ten hiv-positive americans. >> new york has so many infected

people that it has problems of scale when trying to end an epidemic. it buys more drugs than anywhere else to treat hiv infected people. >> woodruff: all that and more, on tonight's pbs newshour. >> major funding for the pbs newshour has been provided by: >> ♪ love me tender ♪ love me true we can like many, but we can love only a precious few. because it is for those precious few that you have to be willing to do so very much. but you don't have to do it alone. lincoln financial helps you provide for and protect your financial future, because this is what you do for people you love. lincoln financial-- you're in charge.

>> md anderson cancer center. making cancer history. >> bnsf railway. >> xq institute. >> supported by the john d. and catherine t. macarthur foundation. committed to building a more just, verdant and peaceful world. more information at macfound.org >> and with the ongoing support of these institutions: >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> woodruff: the first funerals were held today, for the police officers killed by a sniper in dallas last week. thousands attended memorials for three of the five victims:

police senior corporal lorne ahrens; police sergeant michael smith; and rapid transit officer brent thompson. s wife, a fellow officer, spoke at his service. >> brent loves all of his brothers and sisters in blue. i encourage you to stand with me, continue to wear the badge with me, remembering the oath we took. we will not, we cannot, we shall not let the act of a coward break us. >> woodruff: in washington, >> the american civil liberties union sued the police in baton rouge over their treatment of protesters and president obama called in police chiefs, mayors and civil rights activists to talk about building trust between police and minorities. >> ifill: china today rejected an international court's ruling against its claims in the south china sea.

chinese planes made test landings on newly built artificial islands. and in beijing, the foreign ministry said it may impose an air defense zone over the region. >> ( translated ): china firmly upholds the dignity and solemnity of international law. we will by no means agree upon the sheer fallacy that the award from an illegal arbitration tribunal is legally binding. >> ifill: taiwan also condemned the tribunal's ruling. it has similar territorial claims to those of mainland china. >> woodruff: nearly 50 more u.s. troops arrived in south sudan's capital to protect american citizens and property. that follows days of fighting between rival factions, until a cease-fire yesterday. meanwhile, u.n. peacekeepers helped evacuate civilians from the city today. there were also reports that armed men have attacked people trying to flee, and demanded money. >> ifill: and back in this country, wall street took a pause from its recent rally. the dow jones industrial average gained 24 points to close at

18,372. the nasdaq fell 17 points, and the s&p 500 added a fraction. >> woodruff: still to come on the newshour: a new prime minister moves into 10 downing street; who could fill the vice presidential slot for donald trump; new york's daunting task of defeating aids, and much more. >> ifill: the united kingdom has a new prime minister, and her name is theresa may. only the second woman ever to hold the office, may takes over the top job after an extraordinarily rapid turn of events following last month's popular vote to exit the european union. we begin our coverage from london with this report from chris ship of independent television news.

>> less than three weeks as print voted in the e.u. referendum, a new prime minister, theresa may was walking down downing street and a new chapter beginning in british history. not just a new occupant in the building but a new direction as ms. may made clear from her first words in her new job. >> i have just been to buckingham palace where her majesty the queen asked know form a new government, and i accepted. the government i lead will be driven not by the interests of the privileged few but by yours. we are living through an important moment in our country's history. following the referendum, we face a time of great national change. i know because we are great britain that we will rise to the challenge. as we leave the european union, we will forge a bold, new,

positive role for ourselves in the world. >> reporter: theresa may became the 76th prime minister to have the united kingdom and only the second woman to hold the post. after driving from westminster to plals plays, she arrived a few minutes after david cameron tendered his resignation as prime minister. this was the moment theresa may was invited to form a government of her own by her majesty the queen. a new prime minister entering downing street means the old one must leave. david cameron left today, his wife samantha and his daughters and son by his side. >> it's not been an easy journey and, of course, we've not got every decision right, but i do believe, today, our country is much stronger. it has been the greatest honor of my life to serve our country as prime minister of these last

six years and to serve as leader of my party almost eleven years. as we leave for the last time, my only wish is continued success for this great country that i love so very much. thank you. (applause) >> reporter: mr. cameron's final performance in front of m.p.s had happened earlier in the day. his last ever prime minister's questions. cheers first greeted theresa may, and then cheers for the man mrs. may was about to replace. >> mr. speaker this morning i had meetings with minister colleagues and others, other than one meeting this afternoon with her majesty the queen, my diary for the rest of the day is remarkably light. (laughter) >> reporter: today, theresa may was just a spectator. >> nothing is really impossible if you put your mind to it. after all, as i once said, i was the future once. (laughter)

(cheers and applause) >> reporter:ut he is now the past. his job in this place was done. (applause) her job, however is just beginning tonight. the black door of number 10 has a new occupant. >> ifill: joining me now to discuss today's historic events and this remarkable time in the u.k. is sir peter westmacott, a longtime diplomat in the british foreign service. he left his post as british ambassador to the united states earlier this year, and served before that as ambassador to france and turkey. mr. ambassador, welcome. it's been a head-spinning day, a head-spinning time. how are things now doing in britain? what can you tell us about britain now? >> well, it's good to be with you again. i think we're all still a bit shell shocked, but i think the main change that's happened in the less than three weeks -- can you believe it -- since the referendum is even those people who thought it was the wrong outcome and felt the campaign to leave the european union was

based on a lot of misrepresentation and fraudulent fact and so on, everybody has more or less come to terms with the fact that this is going to happen, the negotiations are going to begin, even if many of us believe that at some point before the deed is done the british people will need to be consolidated again either in a general election or another referendum and so on. meanwhile, the political drama has accelerated with great speed. david cameron, prime minister, chose to resign, thought he was going to be there until the 9th of september and, boom, suddenly, in a couple of days, because there was no other candidate but theresa may to succeed him, he finds that the removal van has arrived and he's left and he's been to see the queen. we have a new prime minister and half a new cabinet, not quite half, but a number of senior positions already announced. so i think the mood is one of some surprise, amazement at how quickly things move, and coming to terms with new realities. >> ifill: tell us about theresa may. you know her. tell us what we can expect of

her. >> well, i knew her, saw a good deal of her when she came to stay with us when i was ambassador in france when we had big migration issues and, of course, when she used to come to washington. i think she's a very business-like, no-nonsense person. she's not someone who has cliquey, personal entourages. she is very grounded. comes from a humble, straightforward background, a virk's daughter. i'm a vicar's son, so i can say these things. she does her homework. she likes to get her way. she makes up her mind and she's pretty hard to shift unless you are very, very sure of your ground. she makes a couple of speeches which in the last couple of days are exclusive and quite surprising for somebody who was considered on the right of the conservative party about the importance of the british people coming together and of a government which is for all the people and not just the privileged uh few.

signing that may have surprised a few people but encouraged a lot of people as well. >> ifill: she moved quickly to fill her cabinet including making boris johnson who declined to run for prime minister, to make her foreign minister, and phillip hammond her finance minister and these are the two men to negotiate the brexit negotiations. >> they are and another key player will be the leader of the negotiation, whatever it's called, the department of the withdrawal from the european union, phillip davis. sorted out the ministry of defense when he was defence sherkts' gone to treasury and that will be welcomed. the appointment of boris to is it foreign office was probably as much a surprise to him as

other because after the referendum the result of which seemed to surprise him, he didn't appear to be quite clear what he did next and made a number of statements which suggested nothing was going to change between britain's relationship and the european union. so i think he will be thrilled. he's visibly delighted to go to the front awssments born in the united states of america, partly turkish, partly american, great cosmopolitan, extremely cultured man, speaks lots of languages. he will have a wonderful time in the office and he will not be in the lead of the particular investigations, that will be left to the other ministers largely, i'm not sure on that, but depends on how the prime minister handles it. my guess is her own relationship with angela merkel will be criticalo to is success of the negotiations, too. >> ifill: does david cameron leaving the scene so quickly today, does he leave behind a legacy of failure or success? >> i think some good stuff, some

bad stuff. my own view is the grand coalition that he was bold enough to create when he didn't win a majority in the general election in 2010 was a remarkable piece of political accomplishment. i think the coalition government between the liberals and conservatives worked very well between 2010 and 2015 and smoothed the corners of each party and demon stray tifl the prime minister and deputy prime minister got on well and got good business done, so i think that was a plus. i think the way in which he got the british economy going after the meltdown in 2008 and 2009 was pretty remarkable. the united kingdom has a level of unemployment which is less than half the european union average. we have been growing at the fastest rate of any european country and leading the western states out of recession and cut the deficit more than half. so the economic story will be a plus for david cameron, i think.

running the referendum and winning it on scotland was a plus. people said at the time it was a gamble but in the end a 10-point difference and that kept scotland in the united kingdom, but his legacy will be covered by the fact he tack something of a gamble in organizing this referendum because his own party had become somewhat ungovernable, believed he could win if it came to the referendum being hecialtiond and alas for him and, in my view, many of us, it didn't work out, and, so, the united kingdom is leaving, and i think the united kingdom's decision to vote to leave the european union is inevitably going to be one of the main features of david cameron's political legacy. >> ifill: former ambassador to the united states peter westmacott, thank you. >> thank you. >> woodruff: for republicans, the countdown to their national

convention in cleveland is on, with a major focus on who will be the vice presidential choice. the party's nominee-to-be spent this day working to answer that question. donald trump and indiana governor mike pence, after meeting this morning in indianapolis. pence also appeared with trump last night at a rally: >> we are ready to put a fighter, a builder, and a patriot in the oval office of the united states of america. we're ready for donald trump to be our next president. >> woodruff: alabama senator jeff sessions met with trump today, too, as did former house speaker newt gingrich. he had served as warm-up act in ohio last week. on "fox news" yesterday, he likened the "veep" search to a certain reality show: >> it's a little bit like "the apprentice." you find out sooner or later who the last one standing is. >> woodruff: new jersey governor chris christie huddled with the candidate yesterday, after

campaigning with him monday in virginia. trump told the "wall street journal" yesterday that he wants a running mate who can go on the attack-- to answer the attacks on him. that means going after his democratic opponent, hillary clinton. she appeared today in springfield, illinois, where president lincoln long ago warned of "a house divided." clinton singled out trump. >> his campaign is as divisive as any we have seen in our lifetimes. it is built on stoking mistrust and pitting american against american. >> woodruff: but trump is also taking fire from an unexpected quarter-- supreme court justice ruth bader ginsburg. in recent days, she told "the new york times": "i can't imagine what the country would be... with donald trump as our president." ginsburg made similar remarks in

other interviews, and trump fired back in an early-morning tweet. he said ginsburg "embarrassed all by making very dumb political statements about me. her mind is shot-- resign!" it was amid that furor, that trump's camp said he was aiming to make a final running-mate decision, by friday. and we unpack it all now with susan page, washington bureau chief for "usa today;" and robert costa, national political reporter at the "washington post." and there's a lot to talk about, but, susan, let's start with the vp search on donald trump's part. what do you make of this process, including his children and does it come down to threes three or four people? >> the vice presidential search is usually something that's very coy. they're talking to the people being talked about, say they're not interesting or try to tamp

down speculation about it. in this case, we've had tryouts in front of our eyes about whether they can be at a rally with trump, how they connect with him, so that has been different and i think that's been a good thing. i think we're seeing a debate between donald trump's head and heart. his head says mike pence rounds out his resume and gives him yiewnlty with parts to have the republican party like evangelicals and tea party types that he does haven't the best relationships with, but i bet his heart is saying gingrich or chris christie or guys he would prefer to be around and rather see in that debate against hillary clinton's vice presidential candidate. >> woodruff: robert costa, where do you think donald trump is right now in this? >> i think susan's spot-on with her analysis. what i'm hearing from trump campaign associates is pence is at the top of the list. paul manafort the campaign chairman is also said to be inclined toward the indiana

governor. that doesn't necessarily mean trump has made a decision. he's flying to california tonight with the populous conservative from alabama jeff sessions and is trying to continue to think through his options whether he wants an attack dog or as susan said someone to round out that resume. >> woodruff: so, susan, what does that say to us that it's narrowed down to these four, and including, as robert said, senator sessions from alabama? >> yes, and we're not quite sure why senator sessions was on that list. he was an early supporter, and this may be a way to say thank you to senator sessions for standing with him. it tells us he chose only men. the standard political calculation would have had a woman in that mixes special since donald trump had trouble with women voters, he didn't do that. and it's people who want to be on the ticket with him. he's not coaxing somebody who's reluctant to be on the ticket. he's going to choose somebody who is out there comfortable auditioning for it. >> woodruff: eager for it. roberrobert costa, what do you e

of the process? it strikes me he has his grown children in these meetings. how typical is that? >> it's atypical. trump doesn't function with a normal political organization. he counts on his family for counsel and some advisors. this is someone who operates by making a lot of phone calls, bringing in friends and different people who he's been with throughout his life and soliciting their take on the vice presidential search. he's getting a lot of political calculations thrown his way, but what's most important to trump if you read his books or speak to him himself, he wants a rapport and a connection, someone he can trust. >> woodruff: we'll find out soon enough, we're told it will happen thursday or friday of this week. let's turn to this remarkable series of criticisms that the supreme court justice ruth bader ginsburg launched on donald trump. very unusual. >> never in modern times have we seen these kind of exchanges. when justices in the past have

had a slip of the tongue as sandra day o'connor had on election night in 2000, it hasn't been the attempt seen by justice ginsburg. she said it to the associated press, the "new york times" and this is a message she wanted to get out and it's managed to get the "post" and "times" to editorialize on trump's side. >> woodruff: how is the trump campaign seeing this? how unusual does it throbbing you to hear a supreme court justice going after a political candidate? >> it is unusual. inside the trump campaign in indiana, they are framing the justices comments as condescension that trump may be running as someone who's anti-establishment, they think this battle could be useful to trump to solidify himself as an

outsider. >> woodruff: does something like this have consequences down the road? >> i'm not sure this has big consequences. fink you agree with justice ginsburg you probably think, hey, great, glad she spoke up. if you disagree with her you're probably on trump's side. there will be a lot of important things in this election. this is one of the things that's more interesting than something with lasting political consequences. >> woodruff: i want to ask you about what's been going on already in cleveland this week, that is meetings of different republican committees, one that have to do with the convention, one of them having to do with the platform. it is looking to be a pretty conservative document. what do we know about that? what does that say to us? should we even be paying attention to it? >> the platform is very ideologically conservative. this is a way the trump campaign and the republican national committee believe they can make an overture to tell meant to have the republican party that are disgruntled about trump's nomination and saying trump may

be more centrist and populous in these issues but when it comes to the party we're still down the line, even hard line conservative. what's most important here is the republican national committee is trying to tamp down the revolt or uprising against the delegates and chairman priebus working to make sure that doesn't happen. >> woodruff: they're using this to tamp don disagreement? >> but they're creating problems in the groups. after the autopsy they did in the 2012 defeat, they said they needed to reach out to young people, african-americans, hispanics, gay people. this platform doesn't do any of that. the stance on gay rights and marriage is worse than 2012. as far as millennials, this won't do the republican party any good. >> woodruff: this has language looking for conversion therapy for individuals who are gay.

>> it has language of parents using this controversial technique called conversion therapy for their gay children. that's something even chris christie signed a law banning. >> woodruff: robert, are these things we can expect donald trump to try to implement? >> unlikely. if you look at donald trump, he had a phone call in recent weeks with caitlyn jenner. he's someone who comes out of manhattan. he's comfortable with people of all different backgrounds. he's never been a traditional conservative, but he's running to be the standard bearer of a party moving increasingly to the right. >> woodruff: interesting questions. we'll look at it at the convention next week. robert costa with "the washington post," susan page with "usa today." we'll see you both. thanks. >> ifill: next, we continue our series "the end of aids."

tonight, we go to new york state, where health care providers are trying innovative approaches to bring hiv infection under control. while pushing widespread use of the hiv prevention drug, truvada, they are also trying to expand care to the state's hardest-to-reach populations. correspondent william brangham and producer jason kane continue their reporting, which is supported by the pulitzer center on crisis reporting. >> brangham: this might not look like a breeding ground for hiv, and tina wolf might not look like a typical health worker, but she is. her windblown drives across long island, new york are part of a statewide effort to get out of clinics and medical centers to find hard-to-reach people. wolf recently started a needle exchange program for injection drug users. sharing infected needles is one of the most efficient ways to spread hiv. so each day, she and a small staff pack up hundreds of clean syringes. >> i brought 200, so we need another 200 29-gauge 1/2 ccs.

>> brangham: they load them into her hatchback, and head out. new york, like so many states, has a growing heroin problem-- wolf wants to stop h.i.v. from piggybacking onto that crisis. >> it could very well turn into a new hiv epidemic if we don't get ahead of it. >> brangham: in middle class neighborhoods throughout the island, wolf goes to meet her clients. >> hi! >> hey, how are you? >> good, how are you? >> brangham: today, she meets with this woman, a woman who prefers only to be known as jen. >> it's perfect timing, because i ran out two days ago. >> brangham: most needle exchanges would require jen to come to them, but wolf makes house calls. before these deliveries, jen says she and her boyfriend would re-use needles until they became dull as butter knives. and even though jen knows lots of people with hiv, she's shared needles in the past. >> you're not going to say, oh i'm going to wait until i get a new one. you're going to wait until the person who's in the car with you is done, maybe you'll rinse it

out with the bottle of water in the car, and you get high and you don't think about it. >> brangham: that needle sharing is what public health officials say drove the recent hiv outbreak in austin, indiana, which prompted a state of emergency there. >> i've done things that other people have done, and they've ended up with all different diseases. so, i feel like with tina, i can avoid all that now. >> we will not stop until we add aids to the list of conquered killers. >> brangham: last year, new york governor andrew cuomo pledged $200 million to ramp up efforts statewide to end the aids epidemic here by 2020. their aim is to cut the rate of new hiv infections below the rate of hiv-related deaths. but new york, one of the states hardest hit by the epidemic over the years, still has enormous challenges. nearly one-in-ten people with hiv in america lives here-- that's an estimated 154,000 hiv- positive new yorkers.

approximately 3,000 people are diagnosed statewide every year. and here, minorities bear the brunt of the infections-- an estimated 70% of new cases are among blacks and latinos. jon cohen has been covering hiv/aids for more than 25 years for "science" magazine, and helped us report this series. he says new york's plan is bold, but the state has a tremendous challenge ahead. >> new york has so many infected people that it has problems of scale when trying to end an epidemic. it buys more drug than anywhere else to treat hiv-infected people. it has to track, monitor more hiv infected people. it has to address the failures that are far larger than anywhere else in a way that's just more overwhelming than any other jurisdiction in the country faces. >> brangham: step one for public health workers is finding those who are infected and don't know it-- they're the most likely drivers of new hiv cases. >> i love this outreach here. >> brangham: an estimated 22,000

new yorkers fit that bill. so how do you identify them? >> so what we would want to do is look for hiding spots right now. >> brangham: here in harlem, sometimes that looks like an adult version of "hide and seek." >> so usually you'll see them standing up there, like along the railing. >> brangham: robert gamboa and jose velez work for the harlem prevention center, part of an organization called "icap" out of columbia university. their job is reaching out to gay and bisexual men, encouraging hiv prevention, and inviting them to join the center's research. >> behind the tree over here, that's clearly out of view. >> hmm. oh. >> brangham: they target well- known cruising spots where men often have sex. gamboa sees a couple having oral sex behind a tree, and he doesn't hesitate. >> what up, man? i work with harlem prevention center, we do research studies. >> brangham: each new hiv infection that's prevented saves almost half a million dollars in lifetime treatment costs. dr. wafaa el-sadr oversees

icap-- which also supports global hiv prevention and&2 treatment programs. she says testing as many people as possible, and treating them as quickly as possible, is one of the best tools for ending the epidemic. >> getting those individuals into care, on treatment, for their own benefit as well as of course to prevent transmission from them to others. that's something we have to tackle. and that's usually individuals who are disenfranchised, afraid, in denial, stigmatized, so it's a hard to reach population that we must reach. >> brangham: new york has also pioneered other, data-driven ways to find people in need of hiv care. using medicaid information, the state works in tandem with specialized insurance companies like "amida care" to identify patients who've stopped having tests or stopped refilling prescriptions for their hiv meds. outreach workers then try to get them back into treatment. right now in new york, medicaid covers half the hiv-positive people in the state, so keeping

those people in care is crucial. one estimate said nearly $4 billion could be saved in new york by successfully caring for this slice of the population. so amida care's staff try the phone first: >> no, she didn't answer. >> brangham: if that doesn't work, they'll often head out into the city to go knock on doors-- anything they can do to get people back on track. breaking down the barriers that keep people from consistent hiv care is the next step. a few years ago, that the issue for joe pannell-- he's hiv positive and was given antiretroviral medications, but he was homeless then and addicted to crack and alcohol, so staying on those meds was pretty low on the list of priorities. >> i would go to the doctor and he'd give me medication, i'd sell it. i didn't take it. one of the doctors told me, "that's suicidal." he said, "everything you're doing, it sounds like to me you're trying to kill yourself." hi. >> brangham: but that all changed when he got a roof over his head. new york says this is their

"greatest unmet need"-- helping the estimated 10,000-12,000 hiv positive new yorkers who need housing assistance. joe pannell now lives in an apartment complex run by "housing works," and not only do they provide a home, but residents here can also get their hiv treatment in the same building. >> part of the idea of developing this type of facility was that a person living upstairs, the way i like to say it is, "they can crawl out of bed and they will fall into the program." >> brangham: charles king started "housing works." they provide 241 units for low income hiv-positive people in new york. king was also instrumental in the creation of new york's broader hiv plan. he says homelessness is a clear risk factor for acquiring hiv. >> it doesn't matter what risk category you fall into, if you're a gay man, man who has sex with men, transgender person, sex worker, homelessness magnifies the vulnerabilities that are going to expose you to hiv.

>> brangham: like the majority of the hiv-positive residents in housing works, pannell is now taking his anti-retroviral drugs regularly-- the virus is undetectable in his blood. his life is back on track, he says. long lost family members are reaching out to him again. >> since i came here, all of these things reoccurred in my life. my daughter called me one night, and said, "hi, daddy." i could not believe it. >> brangham: over the last ten years, new york has been successfully bending its hiv/aids curve-- reducing new infections by 40% and reducing the number of hiv-related deaths by even more. whether these are enough to break the back of the epidemic remains to be seen. >> i think we can do it. i think it can be done. i'm not saying we're going to go to zero, but i think we can decrease the numbers substantially. >> brangham: public health advocates say that absent a vaccine or a cure, the challenge ahead is maintaining, and intensifying, these efforts. they argue, ending aids in new york means prevention has to be dialed up and more people

brought into care. the state needs increased housing for the most vulnerable, and sustained lifetime treatment for tens of thousands of people for many years to come. for the pbs newshour, i'm william brangham in new york. >> ifill: tomorrow night, our series on "the end of aids" turns from the epidemic here, to the one in sub-saharan africa, and specifically to rwanda, a nation that's recovered from a genocide, and has now achieved impressive results tackling hiv. >> reporter: at this hospital in a remote northern area of rwanda, a small medical miracle is unfolding. this district-- still in the grips of an hiv epidemic -- has not recorded a single case of mother-to-child h.i.v. transmissions for three straight years. similar progress has been happening throughout rwanda, outpacing many other places in the world, even many in the u.s. >> ifill: that's tomorrow, here on the newshour.

>> woodruff: stay with us. coming up on the newshour, from the creator of new york's highline comes a new public square in cleveland, just in time for the republican convention. but first, how science is increasingly considering the possibilities of medical marijuana as conventional medicine for some cases. science correspondent miles o'brien has the second of his two reports on this for our weekly series, the "leading edge." >> reporter: it's a landmark place, and time, on the long road to bringing medicinal marijuana into the scientific mainstream. the new england treatment access dispensary in brookline, massachusetts, is housed in a beaux art bank building built in the 1920s.

a cathedral of cannabis. paul breeden has been a coming here to treat chronic pain since the dispensary opened in february. >> i've been praying for this day all my life. i've been fighting for this day all my life. i'm a son of a minister, i believe god created marijuana. humans don't know how god works. >> reporter: neta consultant neta is a non-profit, serving about 4,000 medical marijuana customers now. the goal is to supply 10,000 on an ongoing basis. besides dried flowers and buds that can be smoked, they offer pills, vapors, creams, tinctures, brownies, chocolates and lozenges. >> i mean, it's really part of sort of the normalization of medical cannabis, the days of ziploc baggies are over. >> reporter: norton arbelaez is

a neta consultant, an attorney by training, who turned to medical marijuana after he contracted a staph infection ten years ago. >> i had quite a bit of pain. i was prescribed opiate painkillers and i made up a decision, a very conscious decision to not take them. so i had to find a way to medicate otherwise. i did some research and cannabis seemed like a good choice for me. >> reporter: arbelaez believes this classic old bank is brick- and-mortar proof that pot is in emerging from prohibition-- not just legally, but also in the court of public opinion. >> we are coming out of the shadows and into the mainstream. what better way to say that then to be in such a beautiful and historic building. the first, really, of this magnitude on the eastern seaboard. i think it's a harbinger of things to come. >> reporter: five minutes away from the dispensary, another posible harbinger. >> i can think of no better place to host the first annual cannmed conference than here at harvard medical school, so welcome. >> reporter: the first annual personalized cannabinoid medicine conference at harvard

medical school in april. an unprecedented meeting of the minds in the world of medicinal marijuana. and the "father of marijuana research" was here to receive a lifetime achievement award. raphael mechoulam is an israeli chemist who became interested in cannabis when he began his scientific career. >> now i was kind of surprised to find out that the chemistry of cannabis, an important drug in my view, was not well-known. as a matter of fact, we didn't know at that time, i'm speaking of the early '60s, the active compounds had not been isolated in pure form. >> reporter: in 1963, he identified the structure of cannabidiol, c.b.d., one of the most medically important compounds found in cannabis, and in 1964, he isolated the active component of marijuana, tetrahydrocannabinol, t.h.c.

>> i thought that as soon as we know the chemistry and the pharmacology and then the toxicity and if there are any positive effects, companies will go in and take compounds and go ahead with clinical trials, which is true for a huge, huge number of drugs. >> reporter: but this drug is like no other. it was made illegal one year after the 1936 release of a cinematic diatribe against marijuana called "reefer madness." >> it's not so much a substance itself, it's who uses it. the substance was associated with mexican-american and african-american communities. if you look at the precepts of "reefer madness," it's pretty-- i would say embarrassing part of our national history. >> reporter: in the u.s.,

marijuana still remains classified as a schedule-1 controlled substance, the same category as heroin, cocaine and l.s.d., with tight restrictions for researchers. and no accepted use. still, dr. mechoulam pressed on, gradually writing the scientific textbook on marijuana. for years he did not fully understand how and why cannabis works in our bodies. and then, in the early '90s, he had a eureka moment. >> t.h.c. mimics compounds which we make called endogenous cannabinoids, which our brain makes, our body makes, t.h.c. mimics their effects. all of this is called the "endocannabinoid system", and this endocannabinoid system seems to be extremely important. >> reporter: here's how our endocannabinoid system works in the nervous system. the nerves that form the electrical grid of our brain and nervous system are not continuous strands of fiber. instead, there are many gaps in the wiring-- the nerve ends are called neurons; the gaps,

synapses. the electrical current is transmitted from neuron to neuron across synapses by chemical messengers called neurotransmitters. the volume and route of these signals determines what we are thinking, what we perceive and what we feel. our body generates cannabinoids to help regulate the flow of these neurotransmitters. scientists suspect the active ingredient in cannabis thc can either can increase or decrease the flow of the neurotransmitters. and this can have all kinds of impacts on our physical state of being. >> the endocannabinoid system is involved in essentially all human diseases. >> reporter: different endocannabanoid receptors are found in non-nerve cells-- in the immune system, for example. so perhaps it is no surprise that researchers suspect cannabis can do so many things, from fighting cancer, to concussions, to crohn's disease. but perhaps the most dramatic

story of how cannabis might be good medicine is in epilepsy. in the '70s and '80s dr. mechoulam published studies that showed c.b.d. can curb seizures. there was no further research, until parents of epileptic children who did not respond to conventional pharmaceuticals discovered dr. mechoulam's work. >> i do this with two hats. >> reporter: neuroscientist catherine jacobson told her story to the cannabis medical conference at harvard. her seven-year-old son ben has epilepsy. after discovering dr. mechoulam's papers, she started giving ben daily homemade doses of c.b.d. his seizures diminished by 40%. >> but it's excruciating to think about what we went through to get here and what might have happened if we've been able to

do this five years ago or six years ago. i know for a fact he would be a different kid today if he hadn't suffered all that brain damage. >> reporter: her experience with her son and c.b.d. prompted her to redirect her scientific career. she now heads clinical research for tilray, a canadian medical marijuana company trying to turn cannabis into conventional medicine. >> if it can't happen in the u.s., then we're going to make it happen globally. >> reporter: but dr. mechoulam believes the pace of research will increase dramatically if prohibition in the u.s. is lifted. >> people express themselves and say, "we want this to be done." it can be done. it is complicated. it will cost money. it will take time, but it can be done. >> reporter: during his visit to boston, raphael mechoulam visited neta's remarkable dispensary. the father of marijuana research spent a career trying to make this moment-- this place-- possible.

miles o'brien, the pbs newshour, brookline massachusetts. >> ifill: cleveland is getting ready for the republican national convention next week, and a chance to showcase some big changes in the city. that includes a redesign, renovation and revamping of the city's central square. jeffrey brown has the story with production help from our pbs colleagues at wviz-ideastream. >> brown: strike up the band, turn on the fountain, and ask yourself, what makes a 21st century city liveable, viable, even exciting? in cleveland they're hoping part of the answer is "public square." the new version of it, that is: a $50 million project, eight

years in the planning, ten acres in the heart of downtown, re-made into a space for relaxing, meeting up with friends, cooling off on a hot day. >> this is a public space. we own public square. so why would you not fix up our own property? >> brown: all, says mayor frank jackson, with a larger purpose. >> as we reinvent and redefine cleveland and we reinvent and redefine downtown cleveland, public square is essential in that. >> brown: the idea here in cleveland is one that many cities are embracing, or re-embracing-- that the social side of urban life, the sheer pleasure of hanging out with other people in a nice setting, can be an important driver of economic health. >> well-designed public spaces add significant value to a city. >> brown: the landscape architect behind cleveland's new "public square" is james corner, whose firm, "james corner field operations", is today designing public spaces in many cities in

the u.s. and abroad. i met him near his new york office, at his best-known site: the elevated "high-line" park. >> it wasn't that long ago that there was a lot of skepticism about public space, that public space was seen as a waste of taxpayer money, filled with litter, or homelessness, or crime, or just empty space. i think we have seen a renaissance. if you can create these great spaces where people can come together, it's enormously powerful. it affects people's psyche, it affects their imagination, it affects how they relate to other people and it just charges up the positive energy about what it means to live in a city. >> brown: in cleveland, corner was faced with a square that had long served as a transit hub with two busy downtown streets dividing it-- a place to pass through, not linger. but it actually started life as a public commons: this 1936

painting for the w.p.a. arts project imagined the square 100 years earlier. this is where the local militia would assemble. and later, where citizens gathered to pay respects to abraham lincoln after he was assassinated. the "new" idea, then, is actually an old one. >> this is exactly the idea. people will be able to enjoy the park, sit back, have lunch. just enjoy the center of cleveland. >> brown: veronica rivera moved to cleveland as an on-the-ground designer for james corner's group. among much else, construction teams removed a main thoroughfare, restored iconic statues, sculpted elements of the landscape, creating "concert hill," winding paths and new sightlines. all of it creating the illusion of a small, "natural" setting in a large park planned down to the eighth of an inch. >> it's relatively flat. so if you would have walked in and seen everything at the same time it would have been a bit overwhelming.

it would have felt more like a parking lot instead of a park. by using topography we both create an amphitheater or lawn for events and also create these smaller more intimate spaces. we wanted to create that layering effect, that the square can adapt to you walking on your own, but if it's a huge crowd that it feels appropriate for that as well. >> brown: the 15-month construction was captured in this time-lapse video. that followed years of planning overseen by two local civic organizations, "group plan commission" and "land studio." public space these days can cost a lot of money. more than half of what was needed to rebuild the square's surface area came from foundations, individuals and corporations. ann zoller is executive director of "land studio." >> from day one when we started raising money, we not only raised money for capital but we raised money for ongoing programs and maintenance. so it's "build it right," "make sure it's used correctly," and

at the get-go, "raise money for the future program and maintenance." >> brown: this city is on a roll-- most recently with its basketball championship for lebron james and the cavaliers. and there's a building boom downtown. within a few blocks of "public square" are new hotels, a convention center, renovated apartment houses, the large "flats east bank" project, and much more. biomedical companies have been one driver of jobs, and the downtown population is on the rise. the hope now is that "public square" will bring more. but cleveland still has plenty of problems, including one of the country's highest poverty rates. does public square benefit everybody? it's a majority african american city. i look around downtown here and see mostly whites. >> well, i think for this event you have that, but when you come here on a daily basis and watch who takes public transportation, who goes into tower city, who

goes in for work every day, this is a public square. and we don't play off downtown versus neighborhood, black versus white, we don't play off those kind of things. what we do is we invest in the city of cleveland and when we do that we do that for the entire city of cleveland. >> brown: and now, for the republican national convention. the brand new "public square" may be ground zero for protests and demonstrations. the city's going to get a real test. are you worried at all about it? >> no, oh no. look, we do what we do. you should never ask for something and then complain about it. >> brown: i asked architect james corner if he fears what's coming. >> no! i relish that. i mean, i really hope that there is protest and gatherings and public speech in public square.

creating great public spaces is not only about beautification and green spaces and social settings, it's also about platforms for democratic life to play out. >> brown: even in this case, you might have thousands and thousands of people trampling the whole, it's possible it could get violent. >> it's been built in a robust way. i would not be fearful if there are thousands of people there. it can take it. >> brown: maybe so. but few major urban projects have faced such a dramatic test this fast. from cleveland, i'm jeffrey brown for the pbs newshour. >> woodruff: and speaking of cleveland, we will be hosting a convention special all next week, starting monday night. take a look. >> with so much at stake, you need election coverage you can trust. that's why the pbs "newshour" has teamed up with n.p.r. to

bring you primetime coverage of the conventions. gwen ifill and judy woodruff are joined by n.p.r.'s rachel martin for balanced reporting you won't find anywhere else. join us for national coverage of the republican national convention, july 8, 8:00 p.m. central only on pbs and n.p.r. >> ifill: we're really excited about this first for public media. on the newshour online right now, being able to distinguish music from noise may owe more to culture than biological hard- wiring. that's the finding of a new study from m.i.t., and it may settle a centuries-long debate. read about that and much more on our web site, pbs.org/newshour. >> woodruff: and tune in later tonight on charlie rose. kevin rudd, a former prime minister of australia on what the hague's ruling on the south china sea means for the region and for the united states. and that's the "newshour" for tonight. and that's the newshour for tonight.

i'm judy woodruff. >> ifill: and i'm gwen ifill. join us online, and again here tomorrow evening. for all of us at the pbs newshour, thank you and good night. >> major funding for the pbs newshour has been provided by: >> bnsf railway. >> lincoln financial-- committed to helping you take charge of your financial future. >> md anderson cancer center. making cancer history. >> xq institute. >> supporting social entrepreneurs and their solutions to the world's most pressing problems-- skollfoundation.org. >> supported by the rockefeller foundation. promoting the wellbeing of humanity around the world, by building resilience and inclusive economies. more at www.rockefellerfoundation.org.

>> and with the ongoing support of these institutions and individuals. >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. captioning sponsored by newshour productions, llc captioned by media access group at wgbh access.wgbh.org

this is night ly business s stay on track. portfolio, but whattime should you do and? >> why cleveland small business owners have a lot more to think about as the republican convention comes to town. >> next frontier, businesses are trying to drum up sales using the wildly popular mobile game, pokemon go. but at what risk? all that and more for nightly business report for tonight, july 13th. good evening.