US Supreme Court signals doubts over Donald Trump’s citizenship crackdown
President attends proceedings as justices consider one of their most consequential cases
President attends proceedings as justices consider one of their most consequential cases

Ruling avoids substance of citizenship issue but focuses on disputes between administration and lower-level judges

Case could determine the future of the US president’s global trade agenda

Democratic attorneys-general say president exceeded authority after Supreme Court struck down original levies

About 40 briefs have been filed challenging signature policy ahead of showpiece hearing

US trade policy hinges on obscure laws after Supreme Court ruled previous levies illegal

Uncertainty will linger as the president tests alternative legal options