DAO And The Badge.
The guns have been with us now for over a decade in police service, and they have become very popular in that venue, The Border Patrol issues a .40 caliber DAO, the Beretta 96D, to its agents. The RCMP issues DAO Smith & Wesson 9mms, the full size 16-shot Model 5946 (primarily for uniformed wear) and the compact single-stack 3953 (primarily for plainclothes personnel). Chicago PD, the second largest police department in the nation, allows only DAOs on the street -- SIG, Smith, Beretta or Ruger -- in 9mm or 45 ACP.
NYPD, America's single largest department, has primarily three brands of 9mm autos in the field. They consider the Glock a DAO, which Chicago apparently does not and the Glock 19 is far and away the most popular duty weapon in the Big Apple, followed by the S&W 5946 and the SIG P-226 DAO in that order. Their Glocks are fitted with the heavy "New York Plus" trigger module, which brings pull weight up to roughly 12 lbs. per shot.