Civil Protection officers are abusive police officers seen in urban areas on Earth, often referred to as Metro Cops, CPs, or Metropolice whilst Overwatch refer to them as Protection Team(s).  Most of the CPs are ordinary humans who have "volunteered" to join the Combine for better priviledges such as extra rations, better living conditions, an increase in authority, and status over others.  Some rare humans join out of genuine sympathy and identification with the Combine's objectives.  They are not anatomically altered in any way unlike other Overwatch units.