>> dicky: the jimmy kimmel live concert series is presented by mercedes-benz. the best or nothing. >> jimmy: his album is called "pelago." here with the song "chasing after you," ryan hurd and maren morris!

[ cheers and applause ] ♪ ♪ ♪ you come over when your wine's all gone always catch me when i'm not that strong ♪ ♪ then you wind up staying all night long ain't nothin' new ♪ ♪ then i wake up with you on my chest you got a way of making me forget ♪ ♪ girl with you the answer's always yes every time you call ♪ ♪ but i know yeah i know it's a matter of time ♪ ♪ 'till you walk 'till you walk back out of my life ♪ ♪ leave me standing here lonely feeling like a fool ♪ ♪ every time every time you say we're done ♪

♪ you come back to the love you were running from ♪ ♪ don't know why don't know why i let you but i do ♪ ♪ guess i love chasing after you ♪ ♪ listen wish i could quit you but it feels too good ♪ ♪ if i could turn it off you know i would ♪ ♪ but somethin' 'bout you makes me think we could make it after all ♪ ♪ but i know yeah i know it's a matter of time ♪ ♪ 'till you walk 'till you walk back out of my life ♪ ♪ leave me standing here lonely feeling like a fool ♪ ♪ every time every time you say we're done ♪ ♪ you come back to the love you were running from ♪ ♪ don't know why don't know why i let you but i do ♪

♪ guess i love chasing after you ♪ ♪ ♪ ♪ you come over when your wine's all gone always catch me when i'm not that strong ♪ ♪ then you wind up staying all night long ain't nothin' new ♪ ♪ but i know yeah i know it's a matter of time ♪ ♪ 'till you walk 'till you walk back out of my life ♪ ♪ leave me standing here lonely feeling like a fool ♪ ♪ yeaevery time every time you say we're done ♪ ♪ you come back to the love you were running from ♪ ♪ don't know why don't know why i let you but i do ♪

♪ guess i love chasing after you i love chasing after you ♪ ♪ ♪ [ cheers and applause ] >> dicky: the jimmy kimmel live concert series is presented by mercedes-benz. the best or nothing.

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a $500 prepaid card when you upgrade. call today. >> jimmy: i want to thank will ferrell, ryan reynolds, "red notice," check that out. thanks to "science bob," ryan hurd, and maren morris. apologies to matt damon. tomorrow night, our guests are benedict cumberbatch and kevin garnett. "nightline" is next. and if you happen to see ryan reynolds, tell him i'm still confused. thanks for watching, goodnight. this is "nightline." >> tonight, taking the stand.

kyle rittenhouse in his own words. >> why do you need the gun when you go out there? >> i -- i needed the gun because -- if i had to protect myself because somebody attacked me. >> the 18-year-old accused of murder during last year's kenosha protest. the high-stakes courtroom drama. >> don't get brazen with me. >> will it all lead to a mistrial? plus saving paradise. australia's great barrier reef. >> this sprawling natural habitat is teeming with marine life. >> we follow the team working to preserve one of the great wonders of the world before it's too late. >> we've been able to re-establish breeding coral populations within two to three years. and -- ♪ we take you to the big night. the cma awards.

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♪ ♪ tequila herradura. extraordinary awaits. ♪ good evening. thank you for joining us. it was a gamble. kyle rittenhouse taking the stand today in his own defense. the 18-year-old on trial for murder after a deadly encounter during a night of protests last year following the police shooting of jacob blake.

>> i'd like to call kyle rittenhouse. >> reporter: it was a day of explosive turns in the murder trial of kyle rittenhouse. this morning the 18-year-old who shot and killed joseph rosenbaum and anthony huber and injuring gage crojoyce taking the stand in his own defense. >> i didn't do anything wrong, i defended myself. >> reporter: the defense painting him as a concerned citizen protecting private property, giving medical aid, who acted in self-defense. >> so you felt that as a 17-year-old, it was appropriate for you to be out on the streets o kenosha with an ar-15 that night, fair? >> reporter: the prosecution as a vigilante and outsider who took two lives in cold blood. what's happening outside in wisconsin courthouse reigniting conversations around the nation's racial divide, seen by some as a commentary on the justice system at large. >> what i'm suggesting is, if he's acquitted, we're now seeing the law is also saying it's okay to pick up a gun and take the law into your own hands.

>> black lives matter! >> reporter: in december 2020, protests spilled into the streets after 29-year-old jacob blake was shot in the back seven times by a police officer in kenosha, wisconsin. [ shots fired ] >> all my grandson asked repeatedly is, why did the police shoot my daddy in the back? >> hands up, don't shoot! >> reporter: the shooting spark is outrage, protests demanding justice, but turning deadly when armed vigilantes clashed with protesters. among them then 17-year-old kyle rittenhouse from antioch, illinois, who was seen guarding a car repair shop, telling blaze tv he was armed with lethal ammunition. >> we're protecting from the citizens and i just got pepper sprayed by a person in the crowd. >> reporter: after shooting and killing two, injuring another, would turn himself in to police. he's now pleaded not guilty to

six charges, including first degree reckless homicide and first degree intentional homicide and could face life in prison. on the stand, rittenhouse testifying rosenbaum threatened him before the shooting. >> sorry for my language, he screamed, if i catch any of you [ bleep ] alone, i'm going to [ bleep ] kill you. >> reporter: and that he was scared for his life. breaking down in tears as he described the moments leading up to shooting rosenbaum. >> mr. rosenbaum was now running from my right side -- um -- and i was cornered from -- in front of me with mr. zaminski and there were -- people right there -- >> we're going to take a break. >> reporter: the judge pausing

the proceedings. >> the problem with a breakdown like that is, if you're inclined to believe him, you feel sorry for him. if you're inclined not to believe him, you think he's faking it. and so there's always a danger when something big like that happens in the courtroom. this is a case where, at this point, the defense wants to take as few risks as possible. kyle rittenhouse breaking down on the witness stand could be a risk. it just depends on how the jurors view it. but in the end, i don't think him breaking down on the witness stand is going to make or break this case. >> certainly none of us know a man's heart, but you and i have both covered enough trials to know, what was your reaction to the emotion on the stand? authentic? >> no. to be quite honest with you, no. in fact, i was really surprised at the number of people who were comfortable saying that he got emotional. he appeared to be going through something, but i'm not sure if it's authentic or not.

but whether it was authentic or not is secondary to this. we don't know what he was crying about. >> since august 25th, 2020, this is the first time that you have told your story -- >> i object to this. >> reporter: in cross examination, a rocky start for the prosecution. fireworks after the judge asked the jury to leave the courtroom, admonishing the assistant district attorney. >> you are already -- you are -- i was astonished when you began your examination by commenting on the defendant's post-arrest psilence. that's basic law. it's been basic law in this country for 40 years, 50 years. >> when someone chooses not to speak, that's a constitutional right that can't be used against them. fundamental issue. and the judge was basically saying, you are now trying to use that against him, and that's totally improper. >> reporter: the prosecution also seemed to allude to evidence that the judge had previously banned.

>> don't get brazen with me. you knew very well, you know very well that an attorney can't go into these types of areas when the judge has already ruled. >> skirmishes with the judge are dramatic, and they're interesting, and lawyers get riled up about them. but in the end, it's not going to determine the outcome. >> reporter: while the defense team called for a mistrial based on out of bounds questions, the prosecutor continued, taking rittenhouse step by step through the events of that day, pressing him on his decision to go to kenosha in the first place. whether he was expecting to be in danger when he showed up with an ar-15. >> why do you need the gun when you go out there? >> um -- i need the gun because -- if i had to protect myself because somebody attacked me. >> why would you think anybody would do that? >> i don't know. >> reporter: and played this video in court.

attempting to dismantle rittenhouse's argument that he was in kenosha that night to offer medical help. >> you're not a certified emt, you're not an emt of any kind, you weren't on that night, correct? >> yes. >> so you lied to him, correct? >> i told him i was -- i told him i was an emt, but i wasn't. >> reporter: attacking his claim he shot rosenbaum in self-defense. >> joseph rosenbaum never touched you in any way during that incident, correct? >> he touched my gun. >> he didn't touch your body in any way, did he? >> no. if he would have taken my gun, he would have used it against me. >> to use deadly force, you have to have reasonable fear of great bodily injury or imminent death. but in the end, these jurors are going to decide this case by basically saying, has the prosecution proven beyond a reasonable doubt that it wasn't

self-defense? >> reporter: for many, the outcome may speak to larger issues at play. >> you wrote a powerful article about the meaning of this trial beyond what happens to this young man. you made the point about, for you, not just as mr. rittenhouse is on trial, but vigilante justice is on trial? >> absolutely. it's quite interesting to watch these two trials, both the ahmaud arbery trial taking place in georgia, as well as this trial here with kyle rittenhouse. because at the end of the day, they're both about vigilanteism. it's about vigilanteism through the prism of race. if he's found innocent, if he's acquitted, then you're essentially saying everything that precipitated before he started firing into the crowd, into those individuals, wasn't as bad. and i think that sends a very dangerous message. >> reporter: a verdict could come as early as next week.

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crisis series, "saving tomorrow." >> reporter: it might look like paradise from above, but beneath the turquoise waves of the coral sea, picturesque views turn to the barren expanse of the struggling ecosystem. this is the reality of one of our world's greatest treasures, the great barrier reef. this sprawling natural habitat is teeming with marine life, but it's the maze of coral, the heartbeat of the great barrier reef, that sustains the life here. that's why it's so important to win this fight to save the reef. and that heartbeat continues to be under attack from climate change. back-to-back coral bleaching events in 2016 and 2017, and most recently in 2020, have left their mark on parts of the reef where coral was too hot for too long and withe that's the research boat over there we're about to link up. hello, how are you? thanks for having us on board today.

we meet marine ecologist dr. peter harrison and his squad of graduate students near black island reef off the australian coast, an area severely impacted by coral bleaching in recent years. >> we have lost so many adult breeding corals that the production of larvae is now compromised. that's how and why we're intervening. >> reporter: the great barrier reef stretches over 133,000 square miles, is visible from space, and helps fuel area fisheries and tourism. its importance is not in dispute, but for some in australia, climate change is, despite the eroding state of the nation's prize ecosystem. peter's team is hard at work trying to preserve a small coral community through their larvae culture operation. tell me about this project. what are you getting done today? >> so today is the combination of a year of planning and using new styles of delivery of the coral larvae onto damaged

sections of the reef. we collect some of the immense coral spawn that occurs at the sea surface, then we carefully transfer the eggs and sperm and embryos that are developing into floating larval culture pools that are anchored on the reef. those larvae are now ready to settle. >> reporter: the teams of scientists have tens of millions of mike so thattic coral growing in pool. they're trying to emulate the natural brown clouds of coral spawn typical on the reef this time of year. springlike weather conditions are ideal for breeding. that will change once the summer heat rolls through in the coming weeks. >> what we're going to do is pull the pools over to the back end of the boat here, raise them up, and concentrate the larvae, get an estimate of how many million larvae there are. we'll take the samples so we can calculate how many larvae are in the pool -- >> what part of the process are these larvae? >> these larvae are 6 days old, and those larvae are at a point

now where they will want to settle. that's why we're going to put them back on the reef now. >> a successful outcome from today will be a result of many more larvae settling on the reef and growing into new corals than is occurring naturally. >> reporter: peter says his team's replanting efforts elsewhere on the reef have ushered in reclaimed ecosystems, demonstrating the resiliency of coral dependant biospheres under sfabl ocean temperatures. >> we'll be able to re-establish breeding populations within two to three years. those coral communities are now dominating what were really highly degraded reef systems. so we're very dieted about those results. >> reporter: peter's small operation is only part of the solution to revitalize the countless reefs that are struggling in australia's coast. >> in 2016, we saw a 30% drop in coral cover across the whole great barrier reef. they didn't slowly die of starvation. >> two weeks?

that's all it took? >> they cooked. the temperatures that year were about 3 degrees centigrade above the normal summer maximum. >> reporter: dr. terry hughes directs the center for coral reef studies at james cook university in australia. he's been sounding the alarm on the devastating effects climate change is having on the great barrier reef for years. >> we used to worry about the impact impacts of cyclones because they're destructive to coral. now we wish for a cyclone during very hot summers because bleaching has become so commonplace, we now have weather forecasts that predict bleaching in the coming weeks. >> reporter: hughes says public visibility of the reefs' overall health is key, particularly from those whose livelihoods depend on it. >> the great barrier reef today, after five bleaching events, is a checkerboard of reefs that are in good condition and not so good condition. the tour operators know the good spots. and they're quite selective in

where they take people. to ensure that they have a good experience. >> reporter: in 2019, cannes-based "passions of paradise" began planting coral on various parts of hastings reef in addition to running tours for vacationers. >> some reefs we go to that are 11 of 10, they would blow your mind. without a sustainable approach, we don't have anything to show . >> reporter: every bit helps, but it's still not enough. as global greenhouse emissions continue to climb. in the coming years, the new challenge for researchers will be finding ecologically and socially responsible ways to breed heat-tolerant coral that's also cost-effective. >> we're not looking at seeding a few hundred or a few thousands. i's likely that hundreds of thousands or even millions of corals will be required. but there's a lot of knowledge that we have to gain before we get to that point.

>> reporter: back on the water, peter and his team are using the knowledge scientists already have on the inner workings of these organisms. in just one day, they successfully released more than 3 million coral larvae, hoping each spawn finds a place to settle and thrive on the recovering reef. but it's a drop in the bucket. peter knows much more needs to be done to ensure the entire great barrier reef can thrive once again in the decades to come. >> we need real and effective action, internationally and in australia, on climate change and greenhouse gas emissions. otherwise, the future of the reefs looks very bleak. >> our thanks to bri did. t. up next, the biggest names of country music and the biggest night. ♪ cause a country boy's all that i know how to be ♪