Easier than you think but need patiance.
First of all: I really hate this achievement! I enjoyed controlling emergency units and try to never let anyone down or anyone behinde. Because of that I didn't got this achievement on a legit way, so I have to set up a plan to unlock it.
The method is the fallowing. You need one of the fallowing cases:
- Gang War (fighting with clubs)
- Gang War (fighting with fire arms) !!!There is you best bet!!!
- Gun Raid
- Home Invasion
- Bank Robbery
- Crime Organization Meeting
- Drug Lord
In this cases mostly armed criminals committing crimes and they will start a fight before you can arrest or shoot down them and there is your chance:
Send a police car or helicopter or motorybike with two police officers to the spot, then wait. 3 things could happen:
1) The police officers arrest 2 of the suspects and injured the rest. But the police officers remain healty or they just lightly injured (so not heavily injured). In this case you can do nothing. It is wasen't a success. Transport the injured to the hospital and the rest to the jail than try again.
2) The suspects heavily injured booth of the police officers. In this case you have to send another police unit with two officers to the scene then see point "3". NOTE: I played aroung 2-300 dutys in the game because I really liked it, but never happened something like that.
3) The susspects are down (heavily injured) and one of your police officers are heavily injured too. THAT IS YOUR CHANCE!
All you have to do is wait. The heavily injured persons are going to bleed out with time. The not injured police officer will try to give first aid to the suffering people on the scene with no luck, because he or she is not a meddic. You have to wait until your heavily injured officer is dead (a black strip will appear on his or her picture). After that you can send in the ambulance, police, everyone. The dead cop will be transported to the hospital and as soon as you duty is over the achievement is yours!
Sorry if I was too complicated on some points but I want this solution to be perfectly understandable. I hope that was a success. :)