Law enforcement sources tell TMZ ... Crews went to cops nearly a month after posting on Twitter that a high-level Hollywood executive "came over 2 me and groped my privates" at a Hollywood function.

Crews came forward with the allegations following mounting accusations against former movie mogul Harvey Weinstein.

Because the alleged incident, involving a still-unnamed suspect, occurred last year and within the statute of limitations in Cali, it's possible Crews coming forward could trigger a criminal investigation.

We spoke to Terry's wife days after the accusation, and she said there's a reason why rich, powerful men get away with it.