in the line of duty

Before Sunday’s shooting in ‪#‎BatonRouge‬, 60 line-of-duty deaths had occurred in the USA this year. Of those deaths, 28 of the fatalities were firearm related, a 56% increase from firearm-related fatalities at this point in 2015.

in the line of duty

While one is working (used mainly of police officers or soldiers):an inspector’s funeral is given only for those killed in the line of duty