Nate Ramo was a SWAT officer within the Gotham City Police Department, as well as a murder victim.
Batman: Arkham Origins
Nate Ramo, alongside most of his SWAT unit, was undergoing investigation of corruption by internal affairs. Ramo decided to reveal everything that he knew about his teammate's corruption secretly. Unfortunately, one of his teammates, John DeMarco, learned of Ramo's attempted plea bargain, and proceeded to murder him via a hit and run just outside the GCPD. Batman, learned of the hit and run from a police dispatch via Officer Meyer, arrived at Burnley, investigated the event, and deduced DeMarco's involvement from paint residue from his car (as he had briefly crashed into a wall due to losing control of the vehicle while killing him). Batman then tracked DeMarco down to a nearby building alongside the other SWAT members (the dialogue suggested that they were aghast at DeMarco for killing him in front of the GCPD, as they realized it would likely make them seem even more guilty than before), and, after he interrogated DeMarco, left him to be arrested by the GCPD.