I KNOW that my fathers old P-95 or P-90 in 45a.c.p. could fire when the trigger lock was on. it would not fit very well. all you had to do is pull the trigger lock like you would a trigger.
in my state is the same. i only use them if i leave my gun in the truck when i get out to get a drink or some food. besides that i never use them.

I have spare trigger lock keys on my van' s key ring & my atv' s key ring.....never have a problem!!!!!!!!! Brampton Mike [8D]

I hate trigger locks but do recognize that for someone who does not have a better option for securing their firearms they do serve a limited usefulness.
I instead lock my firearms in a secure steel gun cabinet and have the key with me at all times. That thing is only open when I' m removing or returning one of my guns. I like that they are reasonably secure but that I am still able to get to them quickly if I need to.
For those of you that choose to use a heavy duty safe, can you get to your firearms in a speedy fashion or would it take you longer than you would like in a heated situation?

This is one of the reasons that I don' t own a triggerlock.

I don' t own a trigger lock!!!!!! i don' t want any trigger lock on any of my guns!!!!!!the ones that i got with newer guns are far from my guns(trash)!!!!!!!!!and i won' t buy any gun with a built in gun lock!!!!!!!!!!!!