> "To Serve and Protect," is a phrase made famous by the Los Angeles Police De­partment and adopted, in various forms, by law enforcement agencies across the United States.

https://www.policemag.com/articles/to-serve-and-protect-v2

> In February 1955, the Los Angeles Police Department, through the pages of the internally produced BEAT magazine, conducted a contest for a motto for the police academy. The conditions of the contest stated that: “The motto should be one that in a few words would express some or all the ideals to which the Los Angeles police service is dedicated. It is possible that the winning motto might someday be adopted as the official motto of the Department.”

> The winning entry was the motto, “To Protect and to Serve” submitted by Officer Joseph S. Dorobek.

> On November 4, 1963, the Los Angeles City Council passed the necessary ordinance and the credo has now been placed alongside the City Seal on the Department’s patrol cars.

https://www.lapdonline.org/lapd-motto/

I don't know what film you're referring to, but it's been a motto since the 50's, and made official since the 60's.

Huh, yeah you're right. I swear I remember hearing about this on an NPR radio piece about how police really don't need to do anything to protect you.