One of the officers had been on the job four days. One was on his third shift ever. And Derek Chauvin, who pressed his knee into George Floyd's neck for nearly nine minutes, was the field training officer for one of them.
Chauvin, J. Alexander Kueng, Thomas Lane and Tou Thao were responding to a call about a $20 counterfeit bill on May 25 when they detained Floyd, who died while in custody.
The four officers were fired and are now facing charges in Floyd's death.
Here's what we know about their role in Floyd's arrest as well as their lives before and while they were on the force, based on their personnel files.