. >> prosecutor john mcgehee knew he was facing a tough test. >> you had no cause of death. an uphill battle, but it was going to be a real challenge. >> as the trial began, mcgehee presented the prosecution's theory as to how tim did it. >> even though there was no official explanation for how carrie died, the state presented something called, birkin, a method of suffocation designed to leave no marks by sitting on someone's chest, and covering their nose and mouth. >> to support that scenario, the state called one of mcvay's ex girlfriends, katie smitty. >> why are you nervous? >> i'm scared of him. >> katie described an incident one night in 2013. she said she was startled awake by mcvay sitting on her chest. >> i couldn't breathe. he cut off my air. he is a big man. i'm not a very large woman. i couldn't inhale. >> you moved out after that? >> yes. >> the evidence in prosecutor mcgehee's case was largely circumstantial, but he still felt it was strong. he believed mcvay was the last one to talk to carrie. he had her car. he used her debit card, and her body was found jus

. ♪ 10-year-old luke mcgehee is the fife captain. >> how did you decide you wanted to play the fife in 2000, the corps performs patriotic music all over town. ♪tos home, mount vernon, and the national portrait gallery. 13-year-old xavier williams is drum captain. >> normally when we hear and see fife and drum, it's grown-ups. what do they say to you when they think you're 10, you're 13? >> "they're not going to do well at all." >> people are doubting you at first? >> yeah. >> once we start playing, they're, like, amazed. ♪ >> reporter: amazed that a group of kids so young can be so powerful. jan crawford, cbs news, bristow, virginia. >>> and that's the overnight news for this tuesday. for some of you, the news continues. for others, check back later for "cbs mornings." and of course follow us online anytime at cbsnews.com. reporting from natio capital, i'm jerickaca >>> this is "cbs news flash." i'm shanelle kaul in new york. nine people, including four children, were shot monday night in hollywood, florida. one victim is in surgery, and the rest are in stable condition. police say the