In 2011, Cardoza joined the board of directors of the Thoroughbred Owners of California, a group that advocates on behalf of the racehorse owners in the state.
"I sought an opinion from the House Ethics Committee before joining the not-for-profit TOC," Cardoza said.
He acknowledged that he went to the California statehouse to talk to industry groups and lawmakers about state-level legislation that affects the industry, actions previously reported by the nonprofit group California Watch. The story raised questions over whether the activities constituted a conflict of interest. Cardoza said he was just "visiting friends" and his actions did not amount to lobbying.
In his role with the thoroughbred owners, Cardoza led the effort last year to create a coalition called Horse Racing United to lobby the California legislature on racing issues. Cardoza said he is no longer involved with the coalition's efforts in the California statehouse.
"I encouraged various California horse racing industry groups to come together and stop infighting and to form a loose affiliation called Horse Racing United," Cardoza said. "Once the groups came together, I didn't participate any further."
Cardoza left office to take a job in the Washington, D.C., offices of a large lobbying firm, Manatt, Phelps & Phillips, whose client list is broad and in recent years has included gambling companies that own racetracks, lobbying records show.
In 2010, he reported earning between $55,006 and $175,000 from six of his 13 horses, which raced in California and Maryland. Cardoza said he currently has five horses and none of them are racing.
When the House and Senate wrote their first set of modern ethics rules in the 1970s, in response to the Watergate scandal, they expressly prohibited members from engaging in legislative activities that would financially benefit them. But both chambers immediately carved out exemptions to the rule.