Ann Arbor Det. Lt. Matthew Lige told ESPN that police responded to a 911 call around 1 a.m. Wednesday from a woman believed to be Lewis' girlfriend. The woman alleged that she and Lewis had an argument and that he assaulted her at an apartment in Ann Arbor.
Lewis was not at the apartment when police arrived, but spoke to them via telephone and met with officers a few miles from the apartment shortly thereafter. Lewis was not arrested, and the woman did not receive any medical attention for injuries.
"There were no visible apparent signs of injury, but she is claiming that assault occurred," Lige said. "Assault can occur without apparent injury. It wasn't clear if an assault had occurred, so officers released him at the scene."
Police filed a report to the Washtenaw County Prosecutor's Office in the morning, and based on that report the prosecutor's office authorized the misdemeanor arrest warrant. No arraignment date has been set.
In a statement, Washtenaw County Chief Assistant Prosecutor Steven Hiller said his office "will not release information regarding a request for prosecution until the request has been denied or, if a prosecution is authorized, until the arraignment has taken place."
Lewis' agent, Kevin Poston, did not immediately respond to a message seeking comment. Lewis, however, posted a tweet Wednesday afternoon about a half hour after the charges were released, writing, "It's sad that somebody would want to control you so bad they would ruin your life over it."
The tweet has since been deleted.
Lewis is considered a midround prospect in this year's NFL draft. He is scheduled to participate in Michigan's pro day on March 24.
A 5-foot-10 cornerback, Lewis was named to various All-America teams in 2015 and 2016. He holds Michigan's single-season record for pass breakups with 22 in 2015 and was a two-time All-Big Ten player. He was a finalist for the Thorpe Award last season.