The Rio Rancho Municipal Court is one of 81 municipal courts in New Mexico tasked with handling local issues. The court hears traffic citations and arrests, including DWI first, second and third offenses, animal control cases, code enforcement cases, and other petty misdemeanors.

The court has jurisdiction of up to 90 days in jail and a $500 fine in general, but up to 179 days in jail and a $999 fine. (DWI only) Court costs of $49 are added to traffic cases, $39 in non-traffic cases, and limited to $5 in animal control cases. The court has no jurisdiction over civil matters.

Judge G. Robert Cook is the only elected judge, but has two alternate judges that fill in for him, in his absence.

Cook was elected to his third, four-year term in March 2018. The municipal court judge is elected at-large in a non-partisan election to a four-year term. The next municipal court judge election will be March 2022.