Here is the full list of all 21 RICO achievements.
Purchase all the weapons
Get a kill with a side arm, tactical weapon, and a grenade in the same room
Finish three operations losing less than ten health
Survive ten waves in lockdown mode
Complete a case
Complete a case on Hard difficulty
Reach level 14
Neutralise three or more criminals with one stinger in the same room
Knock down a criminal sliding into a room
Knock off 50 masks
Get one thousand kills
Revive another player five times
Complete a daily operation
Get five hundred kills
Revive yourself five times
Complete a daily training session
Survive five waves in lockdown mode
Get twenty melee kills
Clear a room while in slow-mo ten times
Get one hundred kills
Complete a two-player operation