Dallas police said Thursday they have referred their domestic violence case against Johnny Manziel to a grand jury, which will consider whether to charge the troubled Cleveland Browns quarterback on allegations that he attacked his ex-girlfriend.

Police released a statement saying they have asked the Dallas County District Attorney's Office to present a misdemeanor assault case to the local grand jury. Such a charge carries a maximum punishment of one year in jail and a $4,000 fine.

Manziel's attorney, Bradley Beckworth,[url=http://www.officialmlbrangersshop.com/authentic-11-yu-darvish-jer... didn't immediately return an email seeking comment Thursday. Manziel's agent and marketing agency have both dropped him, and the Browns have indicated they will release Manziel as early as March 9, when the league begins its new calendar year.

The 2012 Heisman Trophy winner and Texas A&M star was accused by ex-girlfriend Colleen Crowley of hitting her and threatening to kill her during a night out on Jan. 30. Crowley said Manziel accosted her at a Dallas hotel and later struck her when they drove back to her apartment in Fort Worth.

Crowley said in court documents that he hit her so hard, she temporarily lost hearing [url=http://www.officialmlbrangersshop.com/authentic-3-russell-wilson-jersey.htm... one ear.

Sashi Brown, the Browns' executive vice president of football operations, said at the NFL combine Thursday that the team would not comment further on Manziel's situation.

''I'm not going to comment again on Johnny,'' he said. ''I think, respectfully, we want to give the young man some privacy.[url=http://www.officialraysshop.com/authentic-3-evan-longoria-jersey.ht... Longoria Jersey Our organization has spent enough time talking about him and we need to focus on moving forward.''

A longtime Dallas criminal defense attorney, Pete Schulte, said police handling of the Manziel case was puzzling. Based on Crowley's affidavit, Schulte said police likely had enough information to at least charge Manziel. Misdemeanor cases like the one Manziel is facing are typically decided by police, not a grand jury, Schulte said.

''I think they're giving [url=http://www.officialraysshop.com/authentic-57-jake-mcgee-jersey.html]http://... more of the benefit of the doubt than they give every other citizen they deal with,'' he said.

Crowley requested and was granted a protective order against the 23-year-old quarterback that prevents him from seeing her for two years. The order also requires Manziel to stay at least 500 feet from her home and place of work, and that he pay $12,000 in legal fees.

Crowley alleged she and Manziel had a confrontation in a Dallas hotel room, which eventually continued downstairs to the valet station. She said he forced her into a car and a valet disregarded her pleas for help. The two eventually drove to where her car was parked in front of a Dallas bar, she said in an affidavit. She accused Manziel of getting into the driver's seat and beginning to drive her.

She said she tried to jump out, but he stopped the car, dragged her back inside and hit her.