Buckley Kuhn-Fricker and her husband, Scott, were murdered by one of James Mason's followers. In a rare event, the neo-Mansonite had actually managed to not only find a girlfriend - but to find one gullible enough to believe his idiotic conspiracy theories.
The parents tried to separate their daughter from this obvious bad influence, but she was determined to see him - even to the point of letting him sneak into the family home.
When they discovered the Nazi under their own roof, they attempted to throw him out. He murdered them, then attempted to shoot himself (but failed. James Mason's boys are not known for their bravery at the end.). With this act, he accomplished what his girlfriend's parents had attempted to do but failed: getting her to forever remove him from her life.
Tragically, before murdering his girlfriends' parents he had confessed to another murder - but it seems nobody had thought to involve law enforcement. Had they, two people might still be alive.
After the killing, James Mason's National Socialist Order (then called Atomwaffen) started an advertising campaign to present the murderer as a romantic hero. It is unclear whether Mason's motive is solely to encourage copycat murders or whether there is some deeper agenda he hopes to pursue by getting his followers imprisoned.