(Oxford English Dictionary)
traffic court orig. U.S., a court of law with jurisdiction over motoring offences.
1919 Evening Star (Washington, D.C.) 11 Mar, 24/1 Approval was given lastnight...to the plan...to establish a *traffic court in this city.
21 May 1915, New York (NY) Tribune, pg. 8, col. 4,:
A Traffic Court.
26 March 1916, New York (NY) Times, pf. XX2:
TRAFFIC COURT TO BE
STARTED APRIL 15
Quarters Now Being Prepared
at 300 Mulberry Street--Re-
quires $1,200 to Equip.
The Traffic Court, which was recently determined up in by the Board of City Magistrates, will open April 15, according to the present plans.