My question is - how will the school determine whether a vehicle parked off campus belongs to a student?
Asking campus security to run the plate through the California Law Enforcement Telecommunications System violates state law, which limits the use of that system to law enforcement matters only and not to ensure compliance with administrative school policy.
In either case we do not know whether the students involved are legal adults or minors, which also changes the nature of things. I still do not think that the answer is as simple as "yes they can".
Guaranteed that this school is in a highly residential area and residents have complained over the years that students are taking up all the public on-street parking that residents need to use to park their cars. Many students likely parked their cars in the same on-street spots for days at a time, never moving them and interfering with the ability of tax-paying residents to park their cars. Enough complaints were made that the local community and school tried to arrange some sort of policy to handle it - hence the requirement for students to only park in the approved lot or else face educational sanctions.
If this is a private institution, it is likely that they can educational sanction you for not following their "rules". I think there is a compelling argument to be made, however, for someone parking their car in a legal, public parking spot - regardless of what the school says.
PS - had the same issues at my college (private). They made similar requirements, however, I just constantly made sure my car was never in the same spot for more than a day. Most campus security aren't too bright and can't keep track of several hundred cars while handling their other responsibilities (driving around in golf carts and finding hiding spots to do crossword puzzles, in my case anyway).
Schools are not required to allow any and all legal behavior a student wishes to engage in. Try wearing a tee-shirt with the words "F*** the World" on it, for example...
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If instead of a public high school we are talking about a private high school, it is even more clear that a private school can enforce any rule that doesn't violate the law as a condition of attendance.
It is a private college in a residential area. While students do consume a number of parking spaces, there isn't a single home near the school without its own private garage. In the contract for using the school parking, the school requires that students agree their policies regarding public parking (which I find ridiculous considering that the contract will only be signed by students who intend to use the school's private parking spaces). Nevertheless, student's who haven't applied for the private parking have signed no such document. In regards to checking to see if a car is parked by a student, the school maintains a database of license plate numbers of student's cars who have used their private parking in the past. The school claims that they will run license plates in the neighborhood through this database. I find this to be a bit odd, considering that the majority of students who park on the street likely won't have paid for the private parking in the past. They recently started sending security to the surrounding streets in the morning to wait and see if students park there, so that they can be identified. With all of this said, I am aware that residents have indeed complained to the school about the parking situation. However, there are no signs stating that students can't use the parking, nor are there signs limiting the amount of time that a vehicle can be parked on a given day.
Additionally, I just read through my enrollment contract for the current year in addition to the upcoming year. There is no mention of parking regulations in either contract.
Next time please provide your details up front so that others don't have to guess and then waste their time on irrelevant nonsense, as I ended up doing. Someone else can expend their efforts on your behalf from here on out.