Apparently she went further than declining to press charges, the defendant's lawyer claimed that the victim "'provided photographic proof of an unblemished complexion to SFPD' and filed an affidavit requesting that the investigation be terminated" [0].
I don't understand your expression but I was just quoting a news source without any interpretation implied. I can imagine how such a scenario would hamper the prosecution moreso than someone just not keen on pressing charges.
[0] http://www.sfexaminer.com/sanfrancisco/attorney-for-internet...