President Donald Trump launched his harshest attack yet on Supreme Court Justice Ketanji Brown Jackson, calling her a “low-IQ person” in a Wednesday social media post that escalated his ongoing war with the nation’s highest court following its rejection of his global tariffs policy.

Presidential Criticism Targets First Black Female Justice

Trump used his Truth Social platform to criticize the Supreme Court’s 6-3 decision striking down his tariff program, directing particular ire at the three liberal justices. While he didn’t explicitly name Jackson, Trump referenced President Joe Biden’s nomination of her in 2022, making the target of his criticism unmistakable. Jackson, a Harvard College and Harvard Law School graduate who clerked for Justice Stephen Breyer before replacing him on the bench, has emerged as a vocal critic of the court’s emergency rulings favoring the Trump administration.

The president complained that liberal justices “stick together like glue, NEVER failing to wander from the warped and perverse policies, ideas, and cases put before them.” Trump also expressed frustration over skepticism most justices showed during oral arguments this month regarding his executive order attempting to end automatic birthright citizenship. He attended those arguments personally, marking the first time a sitting president appeared at Supreme Court oral arguments, though he left before the session concluded.

Pattern of Personal Attacks Extends Beyond Court

New York University law professor Melissa Murray noted Trump’s comments fit a broader pattern from his administration of questioning the qualifications of people of color in positions of authority. The president has similarly attacked other Black female public figures including New York Attorney General Letitia James and Fulton County District Attorney Fani Willis, both of whom investigated him. Murray said these attacks “go beyond generalized grievances” and appear designed to label such officials as unqualified diversity hires, despite Jackson’s extensive legal credentials including eight years as a district judge.

Conservative Justices Also Face Trump Criticism

Trump hasn’t limited his attacks to liberal justices. He called Chief Justice John Roberts and his own appointees Neil Gorsuch and Amy Coney Barrett “an embarrassment to their families” after they joined the tariffs ruling against him. In Wednesday’s post, he added that certain Republican justices have “gone weak, stupid, and bad.” Meanwhile, Trump praised Justice Samuel Alito as “incredible” and “one of the best, EVER” in a separate post. The Supreme Court faces several pending cases affecting Trump administration policies, with decisions expected soon on major constitutional questions including birthright citizenship.