"I know there are questions about Antonio," the head coach told reporters. "We take all the situations with our team very seriously. There are some things we're looking into but I'm not going to have any comment on any of the off-the-field situations or questions on that."
Brown was hit with a lawsuit Sept. 10, one day after he signed with the Patriots, that accused him of raping his former personal trainer. Troubling allegations from other people have followed.
Late Thursday night, a woman told Sports Illustrated's Robert Klemko that Brown was sending her "intimidating" texts. Earlier this week, the outlet published a story in which she alleged Brown made an unwanted sexual advance toward her in 2017 while she was contracted to paint a mural in his home.
When asked whether he expects Brown to be in the lineup Sunday for his second contest with the Patriots, Belichick was vague.
"He's on our roster," he said.
Belichick walked out of his press conference moments later as the questions regarding the wide receiver persisted.
In his first public comments since joining the team, Brown said Thursday he was "super grateful" to be a Patriot but wouldn't address questions related to his off-field situation.
Brown caught four passes for 56 yards and a touchdown in his Patriots debut versus the Miami Dolphins.