Here is the full list of all 51 Door Kickers: Action Squad achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Kill 50 bad guys
Get 3 stars in a mission
Kill 3 enemies by blowing up one barrel
Win one mission in Coop
Successfully complete all missions in Chapter 1
Successfully complete all missions in Chapter 2
Kill an enemy with an elevator
3-Star all missions in Chapter 1
3-Star all missions in Chapter 2
Kill 1000 bad guys
Rescue 50 Wounded Policemen
Disarm 30 bombs
Kick Open 100 Doors
Kick Open 1000 Doors
Blow Open 100 Doors
Stun 500 enemies
Kill 3 enemies with one breaching charge
Complete a level without taking any damage whatsoever
Use sniper support to kill 100 enemies
Set 20 enemies on fire
Unlock Chapter 2
Unlock Chapter 3
3-Star all missions in Chapter 3
Rescue 50 hostages
Rescue 1000 hostages
Use sniper support to kill 1000 enemies
Successfully complete all missions in Chapter 3
Kill yourself with your own explosives
Kill 50 Hostages
Use 5 extra lives in the same mission
Resurrect another player 5 times in the same mission
Collect all 20 secret items
Collect your first secret item
Successfully complete all missions in Chapter 4
3-Star all missions in Chapter 4
Unlock Chapter 4
Make 5 VIP Arrests
Successfully complete all missions in Chapter 5
3-Star all missions in Chapter 5
Unlock Chapter 5
Get 100 kills as Assaulter
Get 100 kills as Breacher
Get 100 kills as Shield
Get 100 kills as Recon
Get 100 kills as Agent Fergie