It isn't that they were given the right to violate the charter. It is that those actions were deemed not to violate the charter. Given that this is in the exact same vein, and arguably less intrusive and disruptive than the act of making you stop for the ride check in the first place, I think it is very reasonable to believe that this would also be deemed not to violate the charter.
Actually you are incorrect: the Supreme Court determined that random spot checks were a Charter violation.
Ultimately it will be the Courts that will rule on this law as well, should it pass.