Legal protection for the title "university" in California
Unlike some other countries, there is no strong federal regulation that controls the titles like "University" and "College".  A few states have state level regulations, but federally there isn't any.

By the looking at the number of degree factories in California, I doubt that state of California has strong control over the title as well.  

Some people became professors in regular four year colleges outside of the states with PhD's from these colleges without attending the class once or even visiting the campus - well, there isn't any campus to visit anyway.