Do you know what the back story is? It's interesting that they were all Scientologists (w the noted exception) and I can't help but wonder if the church played a role. Hopefully there is some info online because I think I'm going to go down the rabbit hole!
It's a pretty long story. Here's a brief summary:
O'Leary and Parsons ran the COSMOS mission for awhile, when Alan Walters was the mission holder. O'Leary hosted a Scientology radio show for a year in the late 70s. Planteen was a Green Beret who did two tours in Vietnam, and he met Parsons and O'Leary at COSMOS. O'Leary worked in an elite military intelligence organization during the Vietnam era. Parsons had been a physical fitness instructor in the Air Force.
In the mid-eighties, all three of them fell on hard times financially.
Parsons had been running a field auditor practice out of his home. At the same time, he was investigating LRH and the Church. He interviewed a lot of declared SPs and other folks who were also doing their own investigations. He had already accepted advance payments from several auditing clients to the tune of over $100,000. The church found out about his investigation activities and kicked him out. That made it impossible for him to deliver the services he had already been paid for and he couldn't pay it back.
O'Leary had a young family and he lost his job over a dispute with his employer over benefits that had been promised.
Planteen had his own private investigation business. He got some bad press in the local papers over a dispute with one of his clients. That killed his income stream.
Parsons was introduced to a client by Ken Wagner. The client was a disgruntled, former employee of a local credit union. Parsons used his relationship with that client to glean inside info on the credit union. He took that info to O'Leary and Planteen and the rest is history. They used their military and Scientology expertise to carry out about nine robberies over the following year. The FBI called them the most professional group of bank robbers in the history of the Eastern District of California. There is a LOT more to it. It would make a good movie.