Lets say you have a purse-snatcher working in the area of Broadway and Vine.

It is perfectly reasonable and constitutional to ask a judge, in court, to grant the police the right to use a surveillance camera so that the suspect can be identified.

If the perp is caught, the camera should be removed.

Any film showing other actions, such as the guy smoking a joint, should be erased and destroyed.

If you want to catch pot-smokers, the court order should specify that offence.

Use of surveillance cameras everywhere people go in public is an outrage to libertarians.

Inside a private business such as a store, is different. You will also see signs like "Smile, you being photographed" on the wall. Hense, you were warned.