system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What can the cops do to this man in his car?(Image in comments)
gpt
In the photo you've posted, this is from a DUI checkpoint, so he wasn't pulled over for a moving violation.

The supreme court has ruled the checkpoints constitutional, so they can choose to keep him at the DUI checkpoint for as long as he's willing to stay in the car (in this particular instance, when they determined he wasn't drunk, they allowed him to leave).

If you've been pulled over for a moving violation, they can detain you if you are resisting arrest.

depending on the jurisdiction, even if you've "done nothing wrong" you may lose your drivers license.  When you get your DL, you have to sign documents that say you will do X or Y (example, in California, if you are suspected of DUI, you must submit to a test, either field or blood.  Not doing so (even if you're sober) can make you lose your license).