ECPO is an acronym for Explorer Corporation Police Operations. Originally considered by Charles Clark as a paramilitary force to subdue the United States government, he abandoned the idea when the US joined Explorer Corporation. Earl Clark reopened the project when research proved that a belief and loyalty system could be mapped onto a human brain. The project was abandoned again as Explorer Bridge neared completion. Michael Planck ordered the creation of the force after Earl Clark’s death at Eris Station, putting first Mark Lamar, then Park Sato in command of the force.