I don't know about locking up but lack of witnesses hurts many women's cases. Look at that evil Dominique Strauss-Kahn and the hotel maid.
On August 22, 2011, prosecutors filed a recommendation for dismissal of all charges against Strauss-Kahn.[56][57] They told the court that inconsistencies in the accuser's testimony led to the decision to recommend all charges be dropped. Their decision to drop the case was based on a number of facts outlined in a 25-page document:
The physical evidence indicated a sexual encounter but did not prove use of force or non-consent;
The prosecution noted multiple instances of the accuser's untruthfulness, including fabricating the story that she was gang raped in her
native Guinea to gain asylum in the U.S. (although her asylum application did not include it);
Changing her version of the events before, during, and after the alleged assault.
Can you say reasonable doubt?