The incident occurred Wednesday, according to a Charlotte-Mecklenburg police report.
The report listed Newton as the victim in the complaint. The woman's name was not listed.
The woman had previously shown up at the Panthers' stadium and been asked not to return. The woman was told not to contact Newton in the future.
Newton declined to talk to reporters on Thursday.
Panthers coach Ron Rivera said Thursday, "I know there was something there, but that's about it. I have no knowledge of that."