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.

---

Example Sentences

County in which a law enforcement vehicle was found to be at fault have risen in recent years.

From Los Angeles Times • May 8, 2026

In this case, an Old World hantavirus was at fault, not the Andes strain that’s responsible for the outbreak on the cruise ship.

From MarketWatch • May 8, 2026

But sources told the New York Times that “outdated targeting data” may have been the cause and the U.S. was at fault.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

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

From Barron's • Feb. 16, 2026

And adding to her irritation was the suggestion—the insane proposition—that somehow Jim had been at fault.

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