For nine months, in a flood of emergency orders, the Supreme Court has allowed President Donald Trump to expand his power.

The justices have permitted Trump to slash the federal bureaucracy, fire the heads of nominally independent agencies and exercise powers traditionally ascribed to Congress.

How much further will the court go?

That will be the overriding question Wednesday when the court hears arguments on the legality of most of the president’s tariffs — the first case to reach the justices in a series of high-stakes tests of Trump’s sweeping claims of authority.

His asserted tariff powers are uniquely dear to Trump, who has repeatedly warned of economic devastation if the court were to rule against one of his signature policies. But the other tests of presidential power could also

See Full Page