Actually, the same thing goes for sexual assault, women often use this to make a man "responsible" for something he didn't made, and yeah, almost the same as "teacher teacher, this guy bullied me" ..
No proof, the victim didn't even made any wrong to him/her, and other think he/she is lying etc, etc.
It's the worst scenario, you can't really do anything, but wait for the other to make a mistake, and prove that you were right.
Good luck