Officially, maybe. But how does it work out in the real world?
Yes, you could look up the voter registration data on the Lynwood city council members. But newspapers do not normally print that information regarding non-partisan elected officials unless it's specifically relevant to the story, which it isn't in this case.
Excuses, excuses. Newspapers normally do not print out that kind of information when a Democrat is caught with his nad in the cookie jar. If they were Republicans, you can be damn sure that the LA Times would make mention of that fact in this story.
For the most part it really does work out that way. There are exceptions, and in some localities (especially the really big cities and counties) it becomes an issue. But in smaller areas and also for local agencies (park districts, school boards, etc.) most voters have no idea which political parties the candidates or elected officials belong to. And when newspapers throw in gratuitous references to such a person's registration status, the newspapers get criticized.
Even the Los Angeles Times usually leaves out that information. Given the Times' biases, when they do make an exception it is more likely to be about a Republican official they don't like, but it's still not that common. And those instances certainly deserve to be complained about. But this particular article does not deserve a complaint, since the Times properly refrained from identifying the officials' party registrations.