"With California's higher emission standards, our community has become a hot bed for catalytic converter theft," [the U.S. Attorney] said in a news release. "Last year approximately 1,600 catalytic converters were reportedly stolen in California each month, and California accounts for 37% of all catalytic converter theft claims nationwide.
[One family that was arrested] allegedly sold over $38 million in catalytic converters
The opening anecdote from an LA Times article in September:
[She] knew something was wrong one morning in October when she turned on her 2008 Toyota Prius and heard a throaty roar, like a plane taking off.
[She] had her wedge-shaped car repaired. But she heard the telltale growl again in January while she was in Sacramento. And again in February, in the parking garage of a Las Vegas casino. And again in March, at home in Los Angeles.
“By the fourth time, I was numb,” [she said]. “I had no emotions left. I was like, ‘Well, this is just how life is now. I guess my catalytic converter is going to be stolen every month.’”