That sucks, I thought the SPCA were good people.
I'm with ART & Lebell. There's no way you can keep working there. These kinds of people never stop doing the wrong thing.
Protect yourself first, then get that place closed. My dogs (the vast majority plucked from the hands of mean and stupid people) thank you.
I do have one question... you said you've been there three years. How long have you realized they were doing the wrong thing? Is the job market really that bad in your area?