Subject: Re: Squirrel lives matter!
Is there no way to test them BEFORE killing them?

No. There's no effective way to test for rabies on a live animal. Which is one reason why people generally aren't allowed to keep certain types of animals as pets, such as squirrels and raccoons. They're wild animals and undomesticated, and are susceptible to carrying rabies. It's cruel and inhumane generally to try to keep wild animals as pets, but for these types of animals specifically it's likely to end badly - because they can't be domesticated (ie. trained not to bite) and any bite is a death sentence for the animal.