The conservative majority of the U.S. Supreme Court is highly likely to continue ruling against President Joe Biden’s policies where they believe he has exceeded his authority as head of the Executive Branch.

After the nation’s highest court ruled in June that Biden did not have the power to simply declare $430 billion in student loan debt forgiven, a majority of justices are likely to find that Biden’s plan to impose higher taxes on the wealthiest Americans reversed as well, according to a Monday report.

While the upcoming autumn court sessions will cover a range of topics, including gun rights, federal agency authority, and the trademarking of the phrase “Trump too small,” it’s the Moore v. United States case that could hold the greatest significance for President Biden. This case revolves around the question of whether Biden has the authority to implement a wealth tax, a policy he has consistently supported.

“Reward work, not just wealth. Pass my proposal for a billionaire minimum tax,” Biden said during the State of the Union address earlier this year. “Because no billionaire should pay a lower tax rate than a school teacher or a firefighter.”

“Biden later proposed a 25% annual tax on all gains to wealth in excess of $100 million in a given year, including unrealized capital gains which aren’t currently taxable. The White House says that the tax would only apply to the top 0.01% of the highest earners. While the proposal faces long odds with a Republican-controlled House of Representatives, it could be nixed permanently if the high court rules such a tax is unconstitutional,” the Washington Examiner reported.

“The specifics of the Moore case don’t involve huge amounts of money, but center around the same issues of taxation and the definition of the word ‘income,’” the outlet added. “Charles and Kathleen Moore, a Washington state-based couple, made a nearly $40,000 investment into an Indian company in 2005 and never received any money or other payments from the company even though it made a profit every year.”

The outlet noted further:

Under the 2017 tax reform law, they learned they were subjected to a mandatory repatriation tax of $14,729. They paid that amount and then filed suit seeing a refund and claiming that the tax violates the constitution’s apportionment clause. 

The Sixteenth Amendment authorizes Congress to “lay and collect taxes on incomes, from whatever source derived, without apportionment among the several states.” That means that the federal government cannot tax stock gains, which are the source of wealth for many billionaires unless those stocks are sold.

For years, progressive leaders including Senators Bernie Sanders (I-VT), Elizabeth Warren (D-MA), and Finance Committee Chairman Ron Wyden (D-OR) have strongly criticized this situation. They have advocated for a wealth-based tax as opposed to solely taxing direct income. An appeals court previously ruled in favor of taxing the Moores in this manner, asserting “there is no constitutional prohibition against Congress attributing a corporation’s income pro-rata to its shareholder.”

However, the Supreme Court has the potential to overturn that decision, thereby prohibiting the repatriation tax and any prospective federal wealth-based taxes.

“The Sixteenth Amendment allows the federal government to impose income taxes without apportioning them among the states,” said Cato Institute research fellow Thomas Berry.

“But courts have always limited those taxes to that word, ‘income,’ and said that word is meaningful. It doesn’t just mean whatever the government wants it to mean,” Berry added.