at fault

Idioms  

1. Responsible for a mistake, trouble, or failure; deserving blame. For example, At least three cars were involved in the accident, so it was hard to determine which driver was at fault, or He kept missing the target and wondered if the sight on his new rifle was at fault. In Britain this usage was formerly considered incorrect but is now acceptable; in America it has been widespread since the mid-1800s. Also see in the wrong.

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Example Sentences

But sources told the New York Times that “outdated targeting data” may have been the cause and the U.S. was at fault.

From Salon • Mar. 14, 2026

But equally, I don’t take the “You are at fault, and of course you should have seen it, and everyone else did,” No. Honestly, I don’t think so.

From The Wall Street Journal • Feb. 21, 2026

Employment agencies deny they are at fault for the abuses, blaming the government for lack of enforcement.

From Barron's • Feb. 16, 2026

Defence barristers previously told the trial there was no doubt Motin was at fault for the collision, but claimed his actions did not amount to gross negligence manslaughter.

From BBC • Feb. 5, 2026

He even wondered who was at fault: him or the monster?

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel