Eli5: how do traffic ticketers know that your car has been in a spot on the street longer than the time limit?



I park on the street in my city and there’s a 2 hour limit for cars without residential permits. How do they know you’ve been parked for longer than the 2 hr limit? Surely they don’t have surveillance on every street and don’t take note of every car’s whereabouts every 2 hours. Do they have some type of device that can tell how long a car has been still?

In: Other

When I used to park on the street they would have someone that would come around and chalk the tires to check for movement.

A police office comes by and marks one of the tires away from the curb with a piece of chalk. If they come back more two hours later and the chalk mark hasn’t moved, they ticket you

Most places I’d bet they are private or essential-ish and needed. Close to important things.

The old fashioned way (in San Francisco) is for the parking officers to drive their little tuk tuks and use a chalk on an extension rod to put a super subtle mark on your wheels that face the street…

Some put a mark on your tire in a particular spot and if they come back later to find the mark in the same spot you didn’t move and therefore have been parked longer than the limit.

Many people just go move their car forward or back every few hours because it can’t be proven by the city that you didn’t leave and come back

It’s actually super simple. In my City at least they carry a piece of chalk and when they walk by they mark the hour on a tire. When they walk by again they glance at the tires. If there is chalk they just do the math.

The chalk thing is old and obsolete. At this point the parking authority have mini computers. They walk along and enter license plate numbers. The computer does the rest.

In Philadelphia once you are on a block for the times amount you must switch sides of the street or go to a different block. Can no longer just move up a spot or two if one comes available.

I don’t know in the US but in Italy you have to signal the time you parked the car with something (can be a simple piece of paper on top of the dashboard) some cars has this [disc](http://it.wikipedia.org/wiki/Disco_orario#/media/File:Modello_disco_orario_italiano.svg) attached on the inside of the front windshield