New Here...Question on Dog Law

I'm new here (I'm not in law nor am I a police officer) I appologise for invading your board! But I don't who else to ask this question and hoped maybe someone here would know. I belong to a German Shepherd board and one of the topics is about "Beware of Dog" signs. Does anyone know what the law is on these signs in MA?

Some people are saying having this sign is a liability. That it could be taken as an admission that your dog is dangerous. I was always under the impression that having this sing was to protect the homeowner in the sense if someone is stupid enough to enter my yard after reading the sign it is out my hands should my dog decide to bite. (my GS puppy wouldn't bite he's 10 months old but my last GS definately would not have let anyone in my house if he didn't know them or if I wasn't there to tell him it was ok).

Thanks for any input on this!