It doesn't matter whether or not surveillance on the bus, on the streets or anywhere «works», since the «cure», if anyone should happen to think there is a need for one is far worse than the «disease».
One can always find a «good» argument in order to justify any oppression. It is so very important, even crucial to liberate oneself from the automatic thinking/response the oppressors have taught us. If one is in favor of surveillance, for instance one supports the oppressors, it is that simple.
Surveillance, like many other things in today’s society isn't there «for our protection», as they claim, but for theirs.
Only easily fooled and order-oriented people accept surveillance.