Peeping Tom

This girl I know lives on the 4th floor of an apartment, and even though it is a fairly good neighborhood, she has been having trouble with a Peeping Tom that lives next door...
Every time she goes out on her balcony to catch a bit of sun while wearing her bikini, this Peeping Tom looks over from his balcony as soon as she removes her top, and stares at her...
She has complained to the superintendent about this Peeping Tom, but he says she must have positive proof before he can do a thing --
She FINALLY got a picture of him while he was staring at her...