Montana Title 44. Law Enforcement § 44-1-1001. Offenses for which patrol officers may make arrests

(a) the offense is committed in the presence of the chief or any patrol officer;

(b) the offense is committed in a rural district and a request for assistance is made by a peace officer; or

(c) the offense is committed in a city or town with a population of less than 2,500 and a request for assistance is made by a peace officer or the mayor of the city or town.

(a) deliberate homicide;

(b) assault with a deadly weapon;

(c) arson;

(d) criminal mischief;

(e) burglary;

(f) theft;

(g) kidnapping;

(h) possession of dangerous drugs;

(i) possession of drug paraphernalia; or

(j) violation of the Dyer Act regarding the transportation of stolen automobiles.