President Donald Trump criticized Supreme Court Justices Amy Coney Barrett and Neil Gorsuch in April after Barrett voted against his tariffs and ahead of a ruling striking down his executive order on birthright citizenship. During the 2025-26 term, Barrett voted against both measures, while Gorsuch joined Chief Justice John Roberts’ opinion invalidating the tariffs and wrote a broader concurrence.
Trump’s reaction renewed a long-running dispute over ideological “drift,” in which a justice’s decisions depart from the expectations of the president or political movement responsible for the appointment. Trump wrote that Barrett and Gorsuch “were appointed by me, and yet have hurt our Country so badly!” Similar disappointment has followed earlier Republican appointments, including those of Earl Warren, Harry Blackmun, John Paul Stevens, Anthony Kennedy and David Souter.
A history of movement
University of Virginia political scientist Larry Sabato estimated in 2005 that about one-quarter of the justices confirmed during the previous half-century proved more moderate or liberal than expected. A 2007 study by Lee Epstein, Andrew Martin, Kevin Quinn and Jeffrey Segal, using Martin-Quinn ideological scores based on voting coalitions in non-unanimous cases, found that nearly every justice since 1937 had shifted ideologically during his or her tenure.
Explanations have ranged from press and social influence to the effects of judicial service itself. In a 1992 Federalist Society speech, Judge Laurence Silberman invoked the “Greenhouse Effect,” a term coined by Thomas Sowell for judges’ alleged susceptibility to journalistic influence. Other scholars have argued that deciding concrete cases can alter judges’ outlooks; Judge Richard Posner said judicial service “is bound to moderate one’s views.”
The conservative pipeline
Trump worked with conservative legal groups, including the Heritage Foundation and Federalist Society, to assemble a public list of potential nominees before the 2016 election. Leonard Leo, then the Federalist Society’s executive vice president, was reported to have developed candidate lists and advised Trump on the nominations of Gorsuch, Brett Kavanaugh and Barrett. One study covering Republican appointees from 1982 through 2021 found that those without a Federalist Society affiliation moved left by about 0.07 points annually on the Martin-Quinn scale, while affiliated justices moved right by about 0.05 points.
The three Trump appointees nevertheless have distinct records. Gorsuch ranks as the current court’s third-most conservative justice by Martin-Quinn scores but has joined liberal justices in eight of his 46 dissents since Justice Ketanji Brown Jackson joined the court. Kavanaugh often aligns with Roberts in merits cases, yet he alone among the court’s center-right members supported Trump in the tariffs case. Barrett sits closest to the center under several measures, and her share of conservative votes in divided cases fell from 65% in the 2020 term to 57% in 2023-24. Whether those results constitute drift depends on whether a justice is assessed by political outcomes or by the legal reasoning used to reach them.