I found a very easy way to kill people in missions it to simply fir the gun at your enemy (Enemies) and wait for them to star firing at you now you can rather call police via phone or if you happen to have a police vehicle use the computer to call backup (they show up much more quickly, and they usually come in pairs.) the result is the cops do all the work for you you can literally sit back, relax, and enjoy the 10-30min show (even though it would take you like 1 min to do it, it's much more fun to watch them do it). this is very useful in the mission hostile negotiations where you must save Roman. mainly because it's unexpectedly shorter than you would expect because SWAT show up, and I mean ALOT of SWAT show up! unfortunately they only clear the first floor and some of the 2nd floor, but the rest isn't that hard.

TIPS:
- Never fire your gun or attack unless all police are gone
- If your really that lazy, lead the cops to the upper floors with a star or two ;)
- Always have a getaway car ready just in case your gun goes off.
- Cheat's can be very useful (F.I.B. Buffalo, Gain Stars, Lose stars, Health, ammo)
- Remember, just because you can only use the police computer once, doesn't mean there is a limit on your cell.

oh dude that is sweet thanks for that info