service dogs in no pets associations

I was recently asked if service (or assistant) dogs are allowed in an association that does not allow pets. What is the answer? Are there any state or federal laws on this?

Tom

DOGS FOR ALL

The answer to the CV dogs issue.
CHICAGO (Reuters) - A friendly dog can make older people feel less isolated -- and it appears to make little difference if that wagging tail belongs to a robot doggie or the real thing. Researchers at Saint Louis University in Missouri compared a 35-pound, floppy-eared mutt named Sparky with AIBO, a far-from-lifelike robot dog, to see how residents of three U.S. nursing homes would respond. "The most surprising thing is they worked almost equally well in terms of alleviating loneliness and causing residents to form attachments,"

http://news.yahoo.com/s/nm/20080227/tc_nm/robot_dog_dc_3
Down, down, I’m just the messenger. Medical proof is proof! I hope the robot doesn’t bark.