That was a big fat fail

If they are coming in at night, motion lights will surprise them and either let them see better for what they are looking for or startle them into leaving. They work only once though, they get used to them and next time they are usually not put off. But, combined with signs and cameras, with the added "smile, you are on camera", it keeps the honest ones out. I know booby trapping is illegal, but, what about some kind of Mcgyvered fire cracker loud noise situation that pops when something is tampered with....no harm in that.