Well, it's our beloved militia
Every month there are news of some of that bastards shooting someone etc. Like one guy in Far East getting drunk, going to a local shop/canteen for more, refused or something, he goes back home, takes his 12 gauge semiauto and shoots 6 persons. He didn't even get arrested!
Here in Moscow a car cuts down another, with Militia "officer" inside, on a traffic light. A sick bastard jumps out and shoots the whole clip from his PM, making two (!!!) holes in offender's car and wounding a person in a car passing by. Not arrested too, only removed from service for some time.
About subway cops: it's a kind of propaganda campaign I think. Ordinary militia tried to find some flaws from "underground rats". Usually "rats" are doing their job fine, they immediately react when I report pocket-thieves etc. They don't even take anything from drunks. Once I was led to a camera for being extremely drunk, the sergeant just kept me there until I got sober enough not to fall on the rails and let me go...
But I am a male 190cm tall and about 100kg, so they act with some respect... OTOH once militia patrol robbed me at the Three Stations square, took my passport and other papers, cell phone and money... Needless to say that I didn't find them... At the same place (there are three huge railway stations there), when I went to a local Militia station to report this, I met two guys from Urals who were searched by a patrol at daytime and about $2000 (all their salary for 2 months somewhere in the North) disappeared! There are 3 railway militia units at that place, 2 city militia departments plus "rats" from subway: you simply can't tell where this patrol is from...
Again OTOH I never had any problems with militia when I was sober (this happens sometimes, seriously!

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