The video started as a tourist's souvenir of a trip to Times Square and ended up in the spotlight at a former police officer's trial.
The July 2008 footage drew more than 2.1 million online views before jurors saw it Monday, at the start of Patrick Pogan's trial on charges of assaulting a bicycling activist and lying about it.
Pogan's trial showcases the growing prevalence of witness and surveillance video in law enforcement in an era of YouTube and cell phone cameras. But Pogan's case examines how complete a story such videos tell.
Prosecutors paint the roughly minute-long footage as evidence that he summarily bodychecked the cyclist to the ground. Pogan's lawyer says the clip doesn't show the full picture of what happened.
The video in the Pogan case allegedly shows the then-rookie officer striding toward rider Christopher Long, a participant in a Critcal Mass cycling demonstration, and shoving Long off his bike on July 25, 2008. Officers wrestled with the Long, before handcuffing him. He wasn't seriously hurt. Pogan's report said Long purposefully rammed him. The cyclist was charged with resisting arrest and other offenses.
The sponsors of the cycling demonstration paid Florida tourist Asam Ishmail $310 for his video and posted it on YouTube.
The charges against Long were dropped. Pogan, who resigned from the force in February 2009, is charged with offenses including assault and falsifying business records.
"Not only did [Pogan] push Christopher Long off his bike - he pushed him right into New York's criminal justice system," Manhattan Assistant District Attorney Ryan Connors told jurors in an opening statement.
Defense lawyer Stuart London said Pogan just acted on instructions to stop cyclists if they broke traffic rules during the freewheeling monthly demonstration, known as Critical Mass.
A supervisor wrote Pogan's report, London said. And he said Long - who sued the city and reached a $65,000 settlement over the incident- ignored a signal to halt, made an obscene gesture and otherwise "orchestrated" the confrontation in ways the video didn't show.
"The video does not give you a 360-degree view of what happened here," London said in his opening statement.
Long's lawyer, David B. Rankin, didn't immediately return a call Monday.
Pogan, 24, faces up to four years in prison if convicted.