I don't know if what I do is stupid or helps or even is that much of a worry with raccoons. When I catch ground squirrels and have to dispatch them via the trashcan drowning method, I also put dish detergent in the trash can while I fill it. Ground squirrels carry the plague around here, so the soapy water will kill all the fleas so they don't get out on my dogs. Fleas will come to the surface and escape if you don't kill them.
Also, my trap won't completely submerge in the large trash can, and the squirrel would always find air at the top.
So, this is kind of hard to do, I try not to look as I do it, but I cut lengths of 1/2" PVC pipe to dissect the cage by slipping one through each square to the other side and use the PVC end caps to keep them from slipping back through. It doesn't matter what end of the cage the critter ends up in, as the squirrels at least, keep going back and forth until they can't and that is the end that goes in first.
It's a nasty business, but has to be done. My shotgun would tear up my cage..........I need a small caliber gun, I would feel better shooting it I think.