According to the Times, Mayor Villaraigosa and Lu Parker have been dating since March.
We reached by phone Bob Steele of the Poynter Institute.
"There's every reason to question whether there are competing loyalties that create a conflict of interest that undermines the credibility of the watchdog," said Bob Steel, Ph.D., DePauw University, and Poynter Institute professor.
Steele saw the fallout when another journalist dated the mayor. Villaraigosa was still married two years ago when he had an affair with KVEA anchor Mirthala Salinas. It stirred questions about his character and the failure of the newsroom staff to disclose early on what he knew. The station hired Steele to conduct ethics workshops.
KTLA News Director Jason Ball told the Times: "Now that we're aware of the relationship, she will no longer be covering local politics."
Yet this weekend she read a story involving the mayor in the run for governor.
"It's unfair to other city officials, to potential opponents of the mayor, if he runs for governor for instance, to special interest groups who are opposing the mayor on certain issues," said Steele.
Steele says Parker, with her wording or inside information, might protect the mayor. "There is no concern as to the ethics whatsoever," said KTLA General Manager Don Corsini.
Tuesday afternoon, Villaraigosa said he did not want to make any comment on his personal relationships. He did say it is a distraction created by the media. He says he's focused on the running of the city. Also, no comment from Lu Parker.