turn a blind eye to

turn a blind eye to (something)

To knowingly ignore some wrongdoing. Can't you just turn a blind eye to this little incident, instead of telling Mom and Dad? Regulators turned a blind eye to those infractions, and thousands of consumers suffered for it.
See also: blind, eye, turn
Farlex Dictionary of Idioms.

turn a blind eye to

Deliberately overlook, ignore, as in She decided to turn a blind eye to her roommate's goings-on. This expression is believed to come from the siege of Copenhagen (1801), in which Lord Horatio Nelson, second in command of the English fleet, was ordered to withdraw but pretended not to see the flagship's signals to do so by putting his glass to the eye that had been blinded in an earlier battle. His attack led to a major victory. Also see turn a deaf ear.
See also: blind, eye, turn
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • turn a blind eye
  • turn a blind eye to (something)
  • turn a blind eye/deaf ear, to
  • stone blind
  • stone-blind
  • big eye
  • black eye
  • a black eye
  • cock an eye at (someone or something)
  • blind drunk
References in periodicals archive
For example, I wasn't convinced by the logic and evidence for the claim that Finley's three-ball-walk rule, which he proposed as a measure to increase offense, was similar to "the decision made by owners in the 1990s to turn a blind eye to the players' bulking up through steroid use." Foremost, the statement wasn't incorporated naturally into the text and I was unclear, in multiple ways, as to the true similarity of the three-ball-walk rule and steroid usage--pitchers were just as likely to use steroids as were power hitters, suggesting that increased offense was not a goal pursued by owners when they addressed steroid usage, and I am unaware of public statements by owners that they would turn a blind eye to steroids to increase offense.
Charlie Finley
It always intrigues me that more often than not, those that oppose low flying seem to turn a blind eye to the low-flying aircraft that take them on their holidays, causing constant and certainly more prolonged noise, pollution etc from Manchester, Heathrow and other airports.
Anti-military; yourLETTERS
Wormser explains in some detail how political concerns caused Johnson and succeeding presidents to turn a blind eye to the human rights of blacks despite evidence of lynchings and other atrocities being committed against America's "darker" brothers and sisters.
The Rise and Fall of Jim Crow
A blindfold tied across Nye's face 30 feet above Queen Street was aimed at urging people not to turn a blind eye to the needless toll of sight loss in developing countries.
Around Wales: CARDIFF - NHS founder shows solid support for World Sight Day
So I learned to turn a blind eye to cheating and plagiarism and to give students, especially athletes, extra credit for everything from reading orally in class to remembering to bring their pencils.
Why Johnny can't fail: how the "floating standard" has destroyed public education
We did not turn a blind eye to the butchers of Europe during the darkest days of the Second World War.
Voice of the Mirror: Save these victims from tyrant's evil
Sports writer Hugh Dan Maclennan says he is fed up of being told to turn a blind eye to players' unruly antics.
Pundit writes shinty off!
He added: "They would rather turn a blind eye to it.
Care chiefs 'turn a blind eye to abuse'