I hadn't read Sculpin's post before I posted mine. But actually yes a Compliance Department is responsible. Compliance reports directly to the board of directors and even the executives of financial insititutions are scrutinized by Compliance. Employee accounts are monitored even more stringently than customers.
Just remember the employees aren't going to tell you if they see you make a suspicious transaction. Its all behinds the scenes and if you haven't worked in a bank you wouldn't have any idea how sophisticated this program is.
So be careful how you use your bank accounts because its all monitored. Everything.