I assume you're talking about a restraining order. It really depends on the person. Someone that's halfway decent and doesn't want to go to jail and have a record...it can help. They now know you mean business.
It also helps for documentation should you ever have to off them.
Now the next guy may not give a crap about the record/jail and it won't make much difference to them.
Yes there are some that may get pizzed and go off (straw that broke the camel's back) etc.
Is it someone pizzed or some creepy person that just won't go away ?
Good luck regardless.