Dog Health Questions: Dog training vest illegal?

hi is it illegal for a company to not allow my service dog in there store. my dog has a service dog vest. and costco said i couldn't bring him in. do i need some sort of papers to prove that i am disabled and that my dog is my service dog? thanks

So You Want a Guard Dog, Eh? (Basic Dog Training)

Recommended Answer:
Ignore the idiot above me who attempted to answer.

It is illegal for Costco to refuse you in with your service dog. I'm adding a link I hope you find helpful.

I really think you should contact an attorney. You definitely can file a lawsuit for discriminating against you and your dog.

The Importance of Dog Training

• I agree you should speak with an attorney. Costco is very likely in violation of the ADA (Americans with Disabilities Act). Have you spoken with the Costco manager? It's possible that lower level employees are simply ignorant of this law and think they're doing the correct (but wrong) thing.
  
  Good Luck!