He served as head of the NYPD detectives division from 1920 until 1928 when he was removed from office amid charges of police laxity following the murder of underworld figure Arnold Rothstein.
He spent 11 years in the Tenderloin district, where he earned a reputation as a courageous and highly skilled officer, before being made acting captain and took change of the combined detective commands in Brooklyn and Queens.
[1] On December 30, 1909, while stationed in Chinatown, then Sergeant Coughlin and two patrolman were ordered to keep Chinese comedian Ah Hoon under protective custody.
Coughlin publicly defended his conduct during the murder investigation and pointed out that Commissioner Whalen was never able make any more progress then he did, with the case remaining unsolved.
He died at his Lexington Avenue home after a long illness on the morning of September 30, 1951, survived by his nephew and only living relative William Poling.