The section team leads (STLs) are based in T5A. Their office is just south of the North Security hall. Now my experience is that they always back up their staff - which in abstract may be the right thing to do - but clearly if the team leads get repeated feedback about someone then the message will register. Moreover if you make it clear you will be following up the complaint, the STL will feel obliged to talk to the member of staff, and that may have some effect on their future behaviour.