What happens when a foreigner gets a speeding ticket / traffic fine in the United States? I've heard that the issuing officer will demand payment on site or will confiscate the drivers license. That sounds a little too extreme to be true but on the other hand I'm not sure how they would enforce punishment for these infractions on people who can just leave the country.
According to the "Foreign Visitors Driving in the U.S." page on usa.gov:
Searching for "confiscation of driver's license" on google, I found answers to the question "Can police confiscate your drivers license for a speeding ticket?" and it seems that the answer vary by state. So, as we say here, you mileage may vary.
BTW, If you are not paying a traffic fine in the USA, a Failure to Appear warrant will be issued for your arrest. This means that if you are ever pulled over by the police after the warrant has been issued, you will be thrown in jail and will have to work your way through the justice system.