Washington ? The Supreme Court upheld the government’s authority Monday to ban aid to designated terrorist groups, even when that support is intended to steer the groups toward peaceful and legal activities.

The court left intact a federal law that the Obama administration considers an important tool against terrorism. But human rights organizations say the law’s ban on providing training and advice to nearly four dozen organizations on a State Department list squanders a chance to persuade people to renounce extremism.

The justices voted 6-3 to reject a free-speech challenge from humanitarian aid groups to the law that bars “material support” — everything from money to technical know-how to legal advice — to foreign terrorist organizations.