“No cop, no stop” is a popular cycling adage. If a cyclist sees a stop sign, and there is no traffic and no traffic cop, the cyclist frequently applies the “no cop, no stop” principle and rides past the stop sign without stopping. “No-cop-no-stop” has been cited in print since at least 1947, and it originally applied to motor vehicles and for both stop signs and stop lights. The term “no cop, no stop” began to be frequently cited in print since about 1992.
 
A 2004 citation of “no cop, no stop” involved the Internal Revenue Service. The author advised against illegalities on tax returns on the “no cop, no stop” theory that most people don’t get caught.
 
   
Google News Archive
7 November 1947, The Star (Malartic, Quebec), “COME TO A DEAD STOP OR Come To A Stop…DEAD” by Chief A. C. Riddington, pg. 12, col. 2:
This genius of the traffic law violator group might be divided into four different types, to wit: 1) the boisterous safety-be-damned; 2) the casual no-cop-no-stop; 3) the semi-cautious slow-down’s-enough and 4) the cautious just-about-stop type.
 
10 March 1992, Rockford (IL) Register Star, pg. 3A, col. 2:
No cop, no stop
Police used a fake patrol car to try to fake speeders into slowing down, but most motorists said they weren’t fooled.
 
Google News Archive
7 August 1993, Milwaukee (WI) Journal, “If Anglers Must Be Licensed, Why Not Parents?” by James S. Derk, pg. J5, col. 3:
I stood in the parking lot and watched the car make a “no cop, no stop” pause at the road and head north, leaving a trail of light blue smoke.
 
Urban Dictionary
No cop, no stop
The act of running stop signs in rural areas where you know there are no cars coming from the other direction.
(...)
by your mom Mar 10, 2003
 
Dictionary of Roadie Slang
No cop… no stop!—(Come on, we all know this one…)
(...)
Last Revision: 28 May 2003.
   
The Motley Fool
Taxes on Your IRA?
By Roy Lewis
September 24, 2004
(...)
It’s clear that the IRS hasn’t looked into this issue in the past, so you might have just been lucky, but the law is the law, and the “no cop, no stop” method of tax planning is one that can buy you a ton of trouble.
 
Google Books
The Ride:
How to Ride Your Bike from San Francisco to Los Angeles Without Even Dying
By Russell Mendivi
College Station, TX: Virtualbookworm.com Pub.
2006
Pg. 60:
Apparently the “No Cop No Stop” rule only applies to stop signs though. You have to make an actual “stop” for a red light.
 
6 June 2006, Rockford (IL) Register Star, “See the stop sign? Stop,” pg. 5A, col. 5:
I have heard the expression—“no cop, no stop”—and people think it is funny. Is it funny when people die and have their whole lives taken from them?
(Letter by Mike Fortner of Rockford—ed.)