What Is A Mercy Rule?
A mercy rule is an American rule where a game will be determined before it reaches a scheduled endpoint if one competitor has won decisively. It is called the mercy rule because it doesn't allow the opponent to suffer humiliation. It is common in youth sports where "running up the score is considered unsporting".
There is no Mercy Rule in the NFL. This phrase has been flung around the internet, mostly by disgruntled fans who feel that their team was unfairly treated by the league office. The fact of the matter is that there is no Mercy Rule in the NFL, and never has been. The NFL rulebook does not allow the officials to shorten or call the game before it is completed in 60 minutes.
The phrase "There is no Mercy Rule in the NFL" first appeared on a website called Pro-Football-Reference.com on September 7th, 2004. The author of that article was none other than then ESPN NFL Insider Adam Schefter. He was quoting then NFL Vice President of Officiating Al Riveron, who had said as much during an interview with ESPN Radio in Dallas.
Schefter's article was in response to a rumor that had started circulating around the internet at the time - namely, that there was indeed a Mercy Rule in the NFL, and that referees were instructed to show leniency towards certain teams when it came to penalties.
There is no evidence to support this claim, and Al Riveron himself has since denied it. In fact, he's made it clear on more than one occasion that there is no such rule whatsoever.