[matwood]

If safety was the real goal the police themselves would announce checkpoints and speed traps. This gives people a chance to not drink too much or speed in the first place. I've lived in places where DUI checkpoints were all announced ahead of time, and I think for many it was a serious reminder to not drink and drive.

But for many DUI checkpoints safety is not the goal. It's simply a pretext to check everyone's papers.

[victorbjorklund]

That only works if you actually have a DUI checkpoints all the time everywhere. It is a random check because then people need to be careful all the time. If there is a DUI checkpoint 2 times per year in your area you can just avoid driving drunk at those two days per year.

[aerostable_slug]

They do. DUI checkpoints are heavily advertised here in California for exactly that reason — to deter drunk drivers. The only thing they don't do is tell the exact intersection so drunks don't just drink and drive the other direction.

[Whoppertime]

https://www.chch.com/chch-news/police-services-across-ontari... In Ontario they announce R.I.D.E. checkpoints ahead of time, it is always before winter holidays.

[willsmith72]

Like in sports, how before every drug test the athlete is given a heads-up right?

Or is perhaps the chance of a random test at any moment more of a deterrent?