A Harlem law student is a key plaintiff in the class action suit.
"It took to this point for me to say enough is enough, I have to stand up," David Ourlicht said.
Ourlicht says he lost count of all the times he's been stopped and frisked by police for no reason.
"It's a traumatic thing my heart stops every time a police car passes," he said.
He says he'll be taking the stand on behalf of millions of people stopped and frisked by police without reasonable suspicion. Since Mayor Bloomberg took office in 2002 the number of stop and frisks have gone up 700-percent from 97-thousand to a peak of nearly 700-thousand in 2011, 86-percent of them, minorities.
"There's an accumulation of over-powerful evidence that makes an over-whelming case," attorney Darius Charney said.
Charney will argue the case for the Center for Constitutional Rights.
"I hope that after 15 years the NYPD is going to be held accountable for violating the constitution," he said.
City Lawyers will argue that Stop and Frisk has made the city safer than ever.
"Under the Bloomberg decade we have had a 51-percent decrease in murders in the city and we are by far the lowest city for murder," NYPD Commissioner Ray Kelly said.
Convincing the judge of that may be difficult since in pre-trial motions she has expressed skepticism saying, "widespread practice of suspicion-less stops displays troubling apathy towards New Yorkers'... constitutional rights."
"I've been stopped from walking to the store, from the back of my grandmom's house in Brooklyn, I've been stopped from just living my life," plaintiff Nicholas Peart said.
The trial is expected to last at least 8 weeks and include testimony from police officers claiming they had to meet a Stop and Frisk quota. Surprisingly, Commissioner Kelly will not be testifying, but the chief of the Department will.