Supreme Court Wary of Remaking Income Tax

WASHINGTON—The Supreme Court looked unlikely to impose strict new limits on Congress’s power to tax income, with some conservative and liberal justices alike signaling wariness about upending long-settled principles of the federal tax code. 

Tuesday’s arguments involved a relatively small payment required by a one-time charge under the 2017 tax overhaul. Challengers are seeking a ruling limiting income that can be taxed to money “realized” by taxpayers—that is, cash they receive or in some fashion control, as opposed to a mere increase in the value of their holdings.