Two law enforcement officials familiar with the probe said Palmer used profanity and pulled out his police baton, prompting another officer to intervene. Investigators are trying to determine if Palmer threatened the man with the baton, the officials said.
During the encounter, the officers and the man were involved in a physical altercation and the man suffered a broken bone after being tackled to the ground, the two officials said. Palmer did not use the baton during the arrest, the officials said.
Sternbeck said the investigation is focused on Palmer’s actions outside of any physical contact with the arrested man and is not related to the man’s injuries. Sternbeck also confirmed Palmer was the only officer under investigation related to the arrest.
According to a police report, at around 2:14 a.m. on Dec. 5, Palmer and another officer responded to the 1900 block of Second Street NW where they attempted to stop a man for possession of an open container of alcohol. During the arrest, according to the report, the 25-year-old man became “combative.”
The man who was arrested could not be reached for comment.
Reached by telephone, Palmer, 32, who has been with the force for about five years, declined to comment on the incident and referred calls to D.C. police.
Union officials declined to comment on the investigation.
In 2016, Palmer was suspended for 20 days for administration infractions related to the pursuit of motorcyclist Terrence Sterling.
In the early morning of Sept. 11, 2016, Palmer was driving a police cruiser with his partner Brian Trainer in the passenger’s seat when they spotted Sterling, who was speeding and running red lights.
Palmer took off after the motorcyclist, ignoring orders not to chase, and engaged in an unauthorized pursuit, police later said. Palmer eventually pulled the cruiser into an intersection ahead of Sterling.
Trainer was getting out of the vehicle as Sterling began to move toward the car, according to testimony offered during a police administrative hearing about the incident. Trainer opened fire as the motorcycle hit the car door, killing Sterling. The officer later told officials he feared for his safety and the safety of his partner.
An internal investigation determined that the shooting was unjustified and Trainer was eventually terminated from the department. Prosecutors declined to file charges against the officers. Sterling’s family filed a lawsuit and settled for $3.5 million.
Jennifer Jenkins contributed to this report.