What is mpo police officer?

Answer 1

"MPO" refers to "Master Police Officer", a rank used by some departments across the United States, but not all. Typically, an "MPO" is an individual who has at least eight-to-ten years on the job, has served within a variety of units (Patrol, Undercover, Narcotics, Gangs/Organized Crime, etc), and most departments require that the individual be a fully trained Tactical Officer (a PO who is trained to a greatly higher level than "regular POs" in the areas of weapons, particularly long-arms, breaching, small-team work, extremely high-risk situations, and other parts of a SWAT-or-equivalent-Tactical-Team), and the MPO may serve as a member of a Tactical Team, and this rank designation may be maintained should the individual be transferred elsewhere or to another unit, regardless of reason for transfer.

In terms of where the rank of Master Police Officer falls on the spectrum of typical departmental ranking systems, it is generally NOT a civil service supervisory rank, however it is regarded as the highest rank attainable by a street/patrol officer (higher than an officer/deputy/trooper), equivalent in many ways to the rank of Corporal, Although an MPO MAY be authorized by his department to assume command at the scene of an event until the arrival of a higher ranking supervisor, unlike a Corporal or Sergeant an MPO is typically not in a supervisory position in charge of a group of officers.

Hopefully this answers your question. Remember, unlike the military, police ranking systems can vary state-to-state, even department-to-department. There are no "set laws" for how the ranking system must be laid-out, so there exist minor variations to extreme differences between departments.