Brian Laundrie Family Attorney Rips Dog the Bounty Hunter, John Walsh

Dog the Bounty Hunter and John Walsh are getting hammered by the Brian Laundrie family attorney, who says both men are inserting themselves in the Gabby Petito case purely for attention.

Steven Bertolino represents the Laundries and tells TMZ ... "Dusty relics like that Dog and John Walsh need a tragic situation like this so they can clear the cobwebs off their names and give their publicity hungry egos some food."

As we've told you ... Dog joined the manhunt for Brian last month, trekking through some rugged terrain in remote sections of Florida and even injured his ankle in the process.

The search has gotten him a lot of attention, and Dog's seen TV offers start rolling in, with multiple networks showing interest in resurrecting a show with him.

We also asked Bertolino if he feels Dog is impeding the official investigation, by showing up unannounced at Brian's sister's house ... and he said, "That's for law enforcement to determine."

As for John ... the "America's Most Wanted" host has a new TV special about the Petito case and the search for Brian.