in the line of duty

Prepositional phrase

in the line of duty

1. (idiomatic) As part of or while performing official duties, usually of the military or police personnel, or of government officials.
   • 1922, William MacLeod Raine, Man Size, ch. 35:

     "I'd hate to have the Inspector send in a report to headquarters, 'Constable Beresford missing in the line of duty.'"

   • 1965 September 10, "Helping the Widows," Time (retrieved 20 March 2018):

     Last year 88 other U.S. policemen were killed in the line of duty.

   • 2015 December 18, Kekla Magoon, "Review of All American Boy by Jason Reynolds and Brendan Kiely," New York Times (retrieved 20 March 2018):

     Quinn's friends repeat the mantra that Officer Galluzzo was just doing his job, the implication being that mistakes made in the line of duty should be forgiven.

2. Used other than with a figurative or idiomatic meaning: see in,‎ the,‎ line,‎ of,‎ duty.

Usage notes

• Primarily used in relation to job-related dangers or death.