That's a quite serious accusation. Do you have some evidence (from a reputable source) that confirms this?
In CA they will fight like hell to prevent it from ever being investigated. And why would they block an "open" voting process from being investigated? A scandal in its own right.
The article you linked to talks about election fraud (i.e. the rigging of an election), not voter fraud (i.e. a ballot voted by one who is ineligible to vote).
I have seen no evidence to believe that the Californian government is actively suppressing access to voter data for the purposes of covering up a scandal. If you have some, I'm all ears. (Or eyes, as it may be.)