This brings up an interesting point. It's been bounced around on many an internet firearms board that some states supposedly "don't recognize" FOPA. Is this true of Mass, or is there definitive evidence that Mass plays nice where FOPA is concerned?
I've heard horror stories (and without proof of which, that's all they are) that NY and a few other Anti states have put the pinch on people for passing through the state in question while fully in compliance with FOPA.
I always scratch my head on this one, given my hopefully correct understanding that FOPA is a Federal law, as opposed to a state law governing possession in a given state.
Bear in mind, I'm not trying to challenge your statement that FOPA would (should?) protect the person in question, but just seeing if there's case law to fall back on given the screwy gun climate in this state.