A Trump administration policy illegally banned transgender troops from military service, a divided panel of federal appeal court judges ruled on Monday.
The Supreme Court on Thursday allowed Trump to enforce a policy blocking transgender and nonbinary people from choosing passport sex markers.
An icon for transgender activism died at the age of 78 on Monday.
Justice Samuel Alito said the law "looks like blatant viewpoint discrimination."
The Supreme Court will decide whether state bans on "conversion therapy" aimed at protecting LGBTQ minors violate a counselor's free speech rights.
The Justice Department appealed a lower-court order allowing people use the gender or "X" identification marker that lines up with their gender identity.