Speeding can be civil or criminal based on the speed in relation to the posted limits or other parameters...

Example Arizona

Most cases of minor speeding are civil speeding violations.

However, criminal speeding tickets can be issued in these common cases:

    When a driver exceeds 85 mph anywhere in the state
    When a driver exceeds 35 mph while near a school crossing
    When a driver exceeds a posted speed limit by 20 mph in a business or residential area
    When a driver exceeds 45 mph when no speed is posted in a business or residential area