[4] Through an agreement with the United States Customs and Border Protection, the Maine Marine Patrol assists in border protection in the "grey zone", an area including Machias Seal Island which is the object of a two-century old territorial dispute between the United States and Canada.

[4][5] Since 2015 it has quadrupled the number of officers assigned to the grey zone due to a perceived increase in the potential for violence in the area.

Operationally, the Maine Marine Patrol is divided into six geographic sections that comprise two separate divisions.

The divisions are commanded by a Lieutenant with three Sergeants that supervise a section staffed by one specialist (large boat operator) and seven marine patrol officers.

Once hired, a new officer must attend the Maine Criminal Justice Academy for 18 weeks of the Basic Law Enforcement Training Program.