First, transgendered individuals are not "confused".

But given the number of municipalities with ordinances in place that allow individuals to use the washroom corresponding to their gender (over 200 in the US alone - plus several states and any number of school districts) if your concern were justified we'd have seen hundreds (thousands?) of cases of this happening.  Instead, nothing - not a single reported case of anyone using transgender protections to enter a women's washroom in order to commit a crime.

But, I do have a question for you?  How are you going to know?  

And, if this was your daughter would you be willing to send her into the men's washroom?

http://tinyurl.com/z6amznq