Earlier, Williams' attorney, Dennis Cogan, had asked the panel to award his client more than $400,000 over a 10-hour detention on Oct. 31, 2012.
The delay and Williams' subsequent detainment, Cogan said, caused the rapper to miss his flight to an important party to launch his debut album, cost him potential endorsement money, and tarnished his reputation among his fans.
"I'm not saying, feel sorry for his financial situation," Cogan said. "But the law is the law."
But the eight-member panel, made up mostly of white jurors, - took less than two hours to reject those claims, finding that police had not violated Williams' civil rights.
"Although we voted unanimously that Mr. Williams' Fourth Amendment rights were not violated, we feel strongly both the plaintiff and defendant were in the wrong and made mistakes," the panel wrote to the judge. Outside court, jurors declined to comment on what they meant by that.
The 2012 traffic stop near 10th Street and Girard Avenue came at a crucial point in Williams' career.
His first album, Dreams and Nightmares, had just debuted at No. 2 on the Billboard charts and he had agreed to appear at several album launch parties across the country.
He was on his way to catch a private jet to Atlanta for one such event when Officers Andre Boyer and Alvin Outlaw pulled him over.
Testifying Monday, Williams said he immediately suspected he had been targeted because of his race.
"In neighborhoods like where I come from, four black males in a car . . . we're always being asked to be searched," he said.
Boyer and Outlaw told jurors that they flagged Williams because of dark tinting on the windows of his Range Rover.
Boyer, at the time, was under investigation and would later be fired for lying to Internal Affairs investigators about another traffic stop.
In Williams' case, the former officer testified Tuesday, he immediately smelled marijuana coming from the rapper's vehicle.
Williams refused to let them search it. So, the rapper and his passengers, including an off-duty narcotics investigator from Florida and a senior vice president at the Warner Bros. record label, were placed in handcuffs and held until officers could obtain a search warrant.
No drugs were found, Williams passed a drug test, and no one was charged.
Still, said Amanda Shoffel, a deputy city solicitor, neither the city nor its officers owed Williams anything.
"Any reasonable officer faced with those circumstances would have conducted an investigation," she said. "Any officer would have done the same thing."