Is it LEGAL in California to use cheater plugs?

[hbiss]

I am concerned here that there are gaps in what is being described by the OP. There is no analysis of the Branch Circuit wiring method(s) in this Premises Wiring (System). Rather, there seems to be an attempt to get around 250.114.

That's a good question! I've seen rental units that are so bad it would be a waste of time and money to upgrade or do anything with the electrical system. Not that that should excuse something being done. Either fix it or tear it down.

I also believe that installing GFCI receptacles in place of non-grounding receptacles is just a Band Aid.

-Hal