As a landlord in the state of Alabama, do we have to accept an official letter from a physician for an animal at a no pets policy place? Per FHA law
My property management company has started to make tenants register their animal with petscreening.com, it's a 3rd party platform that will do all the work for you at no cost to you. They will determine if the letter is baloney or legit. I would recommend you do the same.
is it against the law to deny them or evict them tho?
It is illegal to require people to register with a service. If the letter is signed by a medical doctor, psychiatrist, psychologist, counselor, therapist or social worker, you must accept it at face value unless you have some legitimate reason to believe it is bogus. If it turns out to be bogus, you can prosecute them criminally.
You should have a well-written Animal Addendum that protects your property and the quiet enjoyment of the neighbors, and that requires humane treatment (such as, no chaining to a tree) and proof the animal is current on their shots. You can require proof of tick and flea treatments. The Animal Addendum can be used for pets and for ESAs. You cannot ask for a higher rent, pet deposit, or non-refundable fee for an ESA animal. You can evict someone who does not follow the rules, causes damage to the property and fails to pay for repairs immediately, or who disrupts the neighbors with barking, aggressive behavior, fecal matter on their lawns, etc. That is assuming you have the Animal Addendum I mentioned.