The system most states use to score moving violations against a driver's record, with a licence suspension when the total crosses a threshold - and an interstate compact that makes an out-of-state ticket count at home.
Most states assign a number of points to each moving violation - speeding, running a signal, following too closely, and so on - and record them against the driver's licence when the ticket is paid or the driver is found responsible. When the points accumulated within a set period cross a threshold, the state suspends or restricts the licence, usually after a warning stage. Points typically expire after a set time, and some states remove points for completing an approved driver-improvement course. A few states have no point system and instead suspend for a set number of convictions.
Paying a ticket is a conviction for this purpose. The consequence that surprises most drivers is not the fine but the points, and the further consequence is the insurance premium, which insurers set from the driving record they obtain from the state. The points-and-insurance cost of a ticket often exceeds the fine many times over, which is the arithmetic behind contesting tickets that are not worth contesting on the fine alone.
A ticket in another state generally follows the driver home. Under an interstate compact adopted by most states, the state where the offence occurred reports the conviction to the driver's home state, which treats it as if it had happened there under its own point rules; a separate compact means a licence suspended in one member state cannot be replaced by simply applying in another. Commercial drivers are subject to a stricter, federally defined set of disqualifying offences on top of any state points.
The time to ask is before paying a ticket, not after, since payment is the conviction that creates the points. A lawyer or, in many places, a traffic-court clerk can tell you whether a reduced charge or a driver-improvement course is available - and for a driver already near the threshold, or a commercial driver, one more paid ticket can be the licence.
Choose your state. Each link opens the directory page for the city in that state with the most currently published law firms in this practice area; a +n beside the city is how many other cities in the state also have one. The list is generated when this page loads, so a state whose listings have lapsed drops out rather than becoming a dead link.