There was a really interesting program about this at the last HSUS conference.
Essentially it looked at a bite as a black mark on the dog, and in many cases similar to what you're talking about, that can be a potential death sentence for a dog who bites, even if that bite is unintentional and non-aggressive.
Their solution was to do everything in the shelter's power to make sure that bite never happens. This is especially relevant in the case you're describing where you have a dog with a known history of excited activity that can lead to unintentional bites, I.E. you have good data that this could occur and can take extra precautions. Some of the items suggested were:
Get defensive gear - Have staff wear light gloves and
arm guards these don't have to be anything special or suited specifically for animals, but in many jurisdictions a "bite" is qualified as breaking skin. Having a barrier that can absorb the skin break on a non-aggressive bite, prevents that "bite". This can either be an all the time thing, or just when working with specific dogs who might have these tendencies. You can also look at dog specific items like soft muzzles, gentle leaders, harnesses, anything that gives you more control over the dog's actions.
Train staff - For aggressive dogs this is especially important but even for play biters, they have specific cues and body language that they give off when they're getting to worked up, so it's important for your staff to have de-escalation techniques and leash handling.
Limit who the dog can interact with - Especially if you have volunteers, limit the people that interact with the dog to just the ones that have the most expertise, or just staff, or just certain people. That way the dog is more comfortable with the handlers, knows better what to expect, and the person working with them is trained to deal with play biting behavior.
Get the dog out! - Two years is forever, even in the absolute best shelter, being stuck in the same cages will make anyone go a little wacky. For cases with energetic or even partially aggressive dogs, if they're deteriorating in the shelter or just visually showing that they need more exercise and stimulation, keeping them in the same environment will just make things worse. If they're not being adopted, the dog needs to go to foster or get transported out.
To answer your question, our shelter would evaluate the bite based on the circumstances and reasoning. We would never euthanize a dog just because a bite occurred unless there were aggression or behavioral issues that were clearly related and not resolvable. That said, for a dog that has been at the shelter for two years because it's "not adoptable" (true or not that could be the perception in court), with a multiple bite history, from an administrative standpoint, that animal is also a huge liability. If that dog were to accidentally bite a potential adopter in the face or bite a child, the legal issues for your shelter could be very expensive.
So again, the solution is, try not to ever get to the point where you've gotten there. Train staff, take preventative precautions, limit interaction, have regular pathway planning for animals especially those who have been at the shelter more than 20 or 30 days, figure out a way to get outside resources in if you have an animal that's stuck.
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Jeff Okazaki
Humane Society of Jefferson County
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