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

It had tested its products, found no pathogens and wasn’t at fault, McAfee said.

From Salon • Jun. 22, 2026

"They were not at fault, it was an accident."

From BBC • Jun. 6, 2026

A debt collector for the Perfect Child told Lopez her insurer was at fault in a call she recorded the next day.

From The Wall Street Journal • Jun. 2, 2026

"This incident went beyond the question of whether individual employees were at fault and exposed a lack of social and historical sensitivity within Starbucks Korea," he said.

From Barron's • May 26, 2026

He’d had no indication otherwise from police investigators that Reggie was at fault in the deaths of Jim and Keith.

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