Nathan Prince said his client never contacted Tallahassee police about the alleged domestic assault incident. He said someone from FSU contacted the police after seeing the woman's allegations of abuse on social media.
Williams, a senior from Davenport, Florida, is being investigated for allegedly assaulting the woman, who is pregnant with the couple's second child. They are no longer living together.
No charges have been filed, but the TPD could continue to investigate the alleged incident without the accuser cooperating, if she chooses not to do so.
"Apparently, FSU passed the information along to the Tallahassee Police Department," Prince told ESPN.com. "There wasn't a formal request by [the woman] to police. I don't know if the administration contacted police and told them they needed to take a look at it."
The TPD said Monday it had received the case Saturday night and immediately assigned it to its criminal investigation division.
Florida State released a statement Monday saying it was aware of the investigation and that Williams' status "will be under review."
On Tuesday, Fisher said he would let the university's statement regarding the investigation stand and refused to answer follow-up questions. He did, however, say Williams will play Thursday night at Louisville but didn't specify if he would start the game.
Williams, the team's leading rusher with 378 yards and seven touchdowns, was in pads and practicing Monday.
Meanwhile, the Florida State Attorney's office for the 2nd Judicial Circuit in Tallahassee last week attempted to interview Williams about a June 23 robbery of an FSU student.
Fisher said the university's statement on Williams covers "all issues" involving the running back.
Mark Schlabach, Brett McMurphy and Jared Shanker of ESPN.com contributed to this report.