run afoul of

Idioms  

1. Also, run foul of. Come into conflict with, as in If you keep parking illegally you'll run afoul of the police. This expression originated in the late 1600s, when it was applied to a vessel colliding or becoming entangled with another vessel, but at the same time it was transferred to non-nautical usage. Both senses remain current.

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Example Sentences

Whatever work your business hires your child to do, make sure it does not run afoul of any federal or local labor laws.

From MarketWatch • May 26, 2026

Stilwell, who refrains from sharing his first name, operates on Catalina Island, a dumping ground for officers who’ve either botched cases or run afoul of their superiors.

From The Wall Street Journal • May 22, 2026

As a result, it is nearly impossible for individuals to sue federal officers, including immigration agents, who run afoul of the Constitution.

From Slate • Apr. 15, 2026

Air Canada has run afoul of its bilingualism mandate in the past.

From BBC • Mar. 31, 2026

In Philadelphia, she heard stories about three different runaways who had run afoul of the law, for these stories were being told everywhere —North and South.

From "Harriet Tubman: Conductor on the Underground Railroad" by Ann Petry