Towing Issues: School parking, california public school, dmv ca

Question
The local high school (California public school) is threatening several students that their vehicles will be towed. The security guard claims it is "staff" parking only, yet, nothing is marked as such. What exactly needs to be marked as "staff" parking...the whole lot at the entrance, the concrete stopper at the front of the space or does a sign/paint have to be on the space itself. Or can they have a guard out monitoring who comes and goes.
Please advise.

Answer
California DMV VC 21113 covers parking on school and other public grounds...

http://www.dmv.ca.gov/pubs/vctop/vc/vc.htm

But under other laws  (VC 22658) they are required to have signs which state what parking is allowed...
BUT I also have to mention that in the school rules which students have to read at the first of the year (at least we did when I went to school) parking was spelled out as to who parks where...

The guard is a good idea and that usually works, but it like anything can have problems also.