Police Officer are servants of the State as enforcers and custodians of f law and order. The constitution recognise that Office as Constitutional.
Army, GSU, Anti-stock, KWS Rangers have less powers outside of emergency situations where Government can confer them special dispensation depending on prevailing needs.
One need to appreciate that a Policer Officer can sanction some of your human rights such as: liberty, association, speech, congregation, movement etc.
They have powers of arrest, search, giving fines, appropriating goods as exhibits etc.
What powers and authority does an army man hold apart from living in a barrack and enjoying subsidised beer at their canteen?