A woman could be jailed and forced to register as a sex offender after her stepchildren saw her topless in her home.
Tilli Buchanan, 27, is battling criminal charges after being charged under Utah's lewdness law.
She stripped down to her underwear and removed her bra after doing DIY in her garage with her husband.
When his three young children asked why she was topless, she responded that if her partner could go bare chested, she could too.
It ended up in front of a court after the mum of the children - who were aged 13, 10 and nine - complained to detectives.
But the case has now started a legal row in the US, after a judge ruled that by exposing her breasts, Buchanan had broken the law.
Legislation in Utah states that lewdness includes revealing “the female breast below the top of the areola”.
"Free the nipple" campaigners have branded the law sexist, saying different standards are applied to men and women.
But in a ruling this week, Judge Kara Pettit brushed away objections to the case being brought forward.
Her ruling said: "The Court finds the government has an important interest in enacting laws to protect the health, safety, welfare, and morality of children, and to prevent them from being exposed to lewdness."
Buchanan's lawyer Randall W. Richards told the New York Times: “If a man can go topless and it is accepted in society, that same privilege should be given to a woman."
He branded the court case "a ridiculous charge".
If she is added to the sex offenders' register, she will not be allowed to go anywhere where there are children.
And Leah Farrell, a lawyer from the American Civil Liberties Union of Utah, said: "When I talk to people about the case I don’t think any of them realized they could be charged for a crime for walking around with their shirt off inside their own home."
