19 year-old Karina Vargas welcomed the New Year watching fireworks with friends in San Francisco, but little did she know that later that night she would play a key role in the murder investigation of 22-year-old Oscar Grant. The video she captured of then Bay Area Rapid Transit officer Johannes Mehserle shooting Grant, along with other witness videos, became a catalyst for multiple protests and the eventual arrest of Mehserle.

Like any other teenager with a camera, Vargas setout to document a fun night out with her friends, but her most memorable footage came on the BART platform that night. Vargas told Youth Radio, “No matter how much time passes, I'm never going to forget it. 2009, that New Years, I'll never forget what I had to witness.” She heard yelling through the open doors of her train car and stepped off to witness police officers pulling young men from the BART. Drawing her brand new Christmas gift up to her eye, she captured two videos of the police action, and says she was standing within just 15 feet of Grant when he was shot in the back while lying facedown on the ground.

Karina Vargas regularly confides in her mother about her experiences that night, "I'll say mom it's just not fair, it's just not fair that I had to see that and it's not fair for him." It was Vargas’ mother who recommended she give the video to local TV news channels, and through only a few interviews with those channels, she has become a reluctant public figure. She’s been stopped in the grocery store and at Starbucks. Some people praise her heroism and others criticize her for seeking publicity.

Vagas says she hasn’t left her house, since New Year’s Day, without bringing her camera with her, and she hopes her documentation will inspire others. "Hopefully with what I've done, maybe some people will try to do good, try to do better and get the truth out." With more people, especially youth, carrying smart phones with high quality cameras, citizens undoubtedly have more surveillance power than ever before, tipping the balance of power in favor of the masses.