“I thought it was illegal to tape someone without their consent?”
I’m not a lawyer, but I think in most jurisdictions only one party to the conversation has to consent. Maryland is a famous exception.
It seems that the taping was a criminal misdmeannor in California punishable by up to one year in jail.
http://www.leginfo.ca.gov/cgi-bin/displaycode?section=pen&group=00001-01000&file=630-638