[Lunar_Lamp]

Perhaps, but I think that this misses an important aspect of those first few examples: safety.

The reason that people are pulled over for speeding, broken tail lights and illegal lane changes are so that they can be convinced to remedy the situation and make things safer. The punishment is not meant to be the only outcome of the incident.

You may well be correct (after all, static speed cameras exist, and apparently have an effect), but personally I'd want to see a fairly detailed analysis to convince me that you are correct.

[sjg007]

People speed, drive with broken tail lights and illegal overtake or change lanes all of the time. Only a small fraction of those offenses are captured by law enforcement. In making a stop, we are trading the safety of the public in general against the safety of the driver and officer from the interaction.