What type of gun do detectives carry?

Usually compact versions of popular semi automatic pistols by the big gun makers (S&W ,Glock, Sig Sauer ,Beretta). Most common L.E. caliber is the .40 S&W ,however 9mm parabellum ,.45 ACP and .357 Sig are still seen in the holsters of detectives and uniformed officers alike. Snub nose .38's are still popular as back up weapons. Some "old school" detectives may still rely on the "snubbie" as their primary sidearm.