Erie County District Attorney Frank Sedita III said his office would present the facts and call witnesses before a grand jury Thursday. The panel of 20 jurors can then decide to bring charges or drop the case altogether.
Buffalo police charged Kane and a 21-year-old cousin, James, with felony robbery and misdemeanor counts of theft and criminal mischief early Sunday after cab driver Jan Radecki, 62, told officers the Kanes beat him up during a dispute over the fare.
Both Kanes pleaded not guilty after spending a couple of hours in jail. The NHL player's attorney, Paul Cambria, says Kane did not commit any crime and will be exonerated.
"Nobody's rushing to judgment here," the prosecutor said. "The case will be presented in a fair and professional manner to an Erie County grand jury and they will make whatever decision they will make."
According to a police report, Radecki picked up the Kanes in Buffalo's nightclub district about 5 a.m. and drove them to a city address, charging a $13.80 fare. The cab driver told police the Kanes gave him $15 and he gave them a dollar back but said he didn't have the 20 cents in change.
"The defendants did then grab the money from the complainant's hand (tearing it from his hands) and began to punch him about the face and head," the report said.
Radecki said his glasses were broken and he was left cut and bruised.
Andrew LoTempio, an attorney for the cab driver, told WGN radio in Chicago on Monday that he thinks Sunday's incident was blown out of proportion.
"There was a dispute over the fee and it just kind of escalated from there," LoTempio told the station.
James Kane's attorney, Daniel Barry Jr., has declined to comment.
Patrick Kane was the first overall pick in the 2007 NHL draft and won the Calder Trophy, given to the league's best rookie, in 2008.
He is due at a U.S. Olympic Men's Hockey orientation camp in suburban Chicago on Monday. A preliminary court hearing that had been scheduled for the same day in Buffalo was postponed.