I personally know of a couple dogs that have died and a couple more that I heard of while working at the vets office while wearing the choke collars and many many more that were injured.

One was a pup in a car, the owners ran into the gas station for a second & the dog got his collar stuck on the seatbelt thing & hung himself to death.

The other was out in the fenced in yard while the owner was in the shed, the dog got his choke collar stuck in the fence & suffocated himself to death.

For this reason my dogs only wear a choke collar if needed for the begining stages of training and only if I am right there with them every second! If I have to leave their side, even for one minute it comes right off.