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

The report suggested possible causes for the premature fuze detonation but determined that military personnel were not at fault.

From Los Angeles Times • Mar. 16, 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

“It points to a process goal—reduce conflict, restore order, keep people safe—rather than a contested diagnosis of responsibility—who is at fault, which agency acted improperly, whether an action was lawful,” Santoro said.

From The Wall Street Journal • Jan. 29, 2026

He sits there, still struggling to absorb the information, feeling awkward, oddly ashamed, at fault.

From "The Namesake" by Jhumpa Lahiri