How do you disconnect the rear hatch lock on a 2003 Buick Rendezvous?

I have a 2003 Buick Rendezvous that drained a new battery. I think the back hatch lock me be stuck. Could this be causing the drain? Is there a fuse or something that I can disconect to see if it is this or the alternator?|||Yes, there should be a fuse for the lock in your fuse box. If you look in your owners manual there should be a fuse location diagram that will show you what each fuse is for!|||If you are not sure if the hatch lock it stuck, LET"S FIND OUT!!!!!! YIPPEE!!! You will need a full-size crowbar and a sledge hammer. Try to pry the hatch open from the outside with the crowbar. Do not give up until you tried three times. If this doesn't work, don't be discouraged, you can do it!!! Next step is to grab that trusty 'ol sledge and try to get that baby unlocked from the inside. Swing as hard as you can and see if you can get 'er unlocked. This may require multiple solid, swift, direct hits. Don't give up until you have given her 15 of those loving pats. If none of this works, you can rest assured that baby is definitely locked.