Uncle Sam could soon have a new way for getting taxpayers to pay up.

Congress could approve a bill next month that would give the State Department the ability to revoke or deny passports for people who are behind on their taxes, the Wall Street Journal reported.

The measure would affect taxpayers who are “seriously delinquent” on $50,000 or more of taxes owed, meaning a lien or levy has been filed for the amount owed. People who are under a payment plan or otherwise working to resolve the debt would be excluded. So would people who are challenging their debts in court.

The change is tucked into a highway funding bill, H.R. 22, that is expected to pass in December, the WSJ reported. If enacted as is, the law would go into effect Jan. 1 and would apply to current debts. Estimates from the Joint Committee on taxation project the move could raise $398 million over 10 years.

It’s not clear who would be most affected. About two-thirds of taxpayers pay more taxes than they owe and receive tax refunds, according to the IRS. But some consumer advocates worry the change would hurt U.S. citizens living abroad, who may rely on their passports for their daily routines.

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