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