Rat Patrol is the name of an Army CID Team, Team 01 lead by Meryl Silverburgh,. Meryl states that they are investigating private military activity for the United States Army Criminal Investigation Department (unknowingly under Patriot orders). Like the PMCs, Rat Patrol uses SOP so that they can share each others senses and operate more efficiently as a single unit. They wear FOXHOUND patches during operations to hide their real purpose. The standard issue weapon for the members of the Rat Patrol, bar Meryl, is the M8, developed by the small arms manufacturer Heckler & Koch (H&K). Although each individual has a different variant of the rifle. Ed, who serves as sniper of the team, is equipped with the sharpshooter variant of the XM8. Johnny "Akiba" Sasaki utilizes the XM8 Carbine. Jonathan also uses the carbine, but with the XM320 Grenade Launcher attachment. Meryl, however does not use the rifle. Instead, she uses two versions of the Desert Eagle: One basic desert eagle and a D.E. with extended barrel and scope.
They are assigned as Solid Snake's contacts in the Middle East, and engage the FROGS army in combat while trying to escape the rendevous point. They later lead the American army to try to capture Liquid Ocelot on the Volta River, but are all incapacited after he gains control over SOP.
They survive the ordeal, and Meryl and Johnny lead an attack on Outer Haven with Snake. Following the ordeal, Ed weds Meryl and Johnny, and Jonathan serves as the best man.
