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Supreme Court · Chief Justice

John Roberts

Republican appointee: Appointed by George W. Bush (R)

Served 2005–present · 20 terms

Confirmed 78–22

Biography

John Glover Roberts Jr. is an American jurist who has served since 2005 as the 17th chief justice of the United States. Though primarily an institutionalist, he has been described as having a moderate conservative judicial philosophy. Regarded as a swing vote in some cases, Roberts has presided over an ideological shift toward conservative jurisprudence on the high court, in which he has authored key opinions.

Source: Wikipedia, CC BY-SA 4.0

Ideology over time

J. Roberts and the 15 justices who overlapped with J. Roberts, 2005–present

−4−20+2+42005201020152020More conservativeMore liberalThomasAlitoScaliaGorsuchKavanaughBarrettKennedyJ. RobertsKaganBreyerK. JacksonGinsburgSotomayor
  • John Roberts
  • 95% credible interval
  • Peer, appointed by a Democrat
  • Peer, appointed by a Republican
  • Court median
How to read this

Martin–Quinn scores place each justice on a single liberal–conservative dimension, estimated from their votes across terms, with scores allowed to shift from one term to the next. Higher is more conservative. The shaded band is the credible interval: wider when the record is thin, especially in a justice’s first terms, and narrower as votes accumulate.

Where J. Roberts sits among all justices

Career average, every justice in the data set

−4−20+2+40.331.50

J. Roberts’s range across terms

Served alongside J. Roberts

15 justices

Closest career average first. Filled dot: the peer. Ring: J. Roberts.

JusticeTogetherCareer avg
Amy Barrett2020–2024career average 0.77 versus J. Roberts at 0.81Anthony Kennedy2005–2017career average 0.68 versus J. Roberts at 0.81Sandra O'Connor2005career average 1.02 versus J. Roberts at 0.81Neil Gorsuch2016–2024career average 1.04 versus J. Roberts at 0.81Brett Kavanaugh2018–2024career average 0.56 versus J. Roberts at 0.81Samuel Alito2005–2024career average 2.00 versus J. Roberts at 0.81David Souter2005–2008career average −0.77 versus J. Roberts at 0.81Antonin Scalia2005–2015career average 2.50 versus J. Roberts at 0.81Stephen Breyer2005–2021career average −1.32 versus J. Roberts at 0.81Elena Kagan2010–2024career average −1.74 versus J. Roberts at 0.81Ruth Ginsburg2005–2019career average −1.76 versus J. Roberts at 0.81Clarence Thomas2005–2024career average 3.40 versus J. Roberts at 0.81John Stevens2005–2009career average −1.81 versus J. Roberts at 0.81Ketanji Jackson2022–2024career average −2.62 versus J. Roberts at 0.81Sonia Sotomayor2009–2024career average −3.27 versus J. Roberts at 0.81

How J. Roberts voted

Every argued case J. Roberts took part in, newest first, with how J. Roberts voted in each: with the majority, in dissent, or in an equally divided Court. A Liberal or Conservative tag is the Supreme Court Database’s coding of who prevailed in the case, not a rating of the justices.

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    Data notes

    The Decisions page’s argued cases with this justice’s vote from the Supreme Court Database. “Majority” includes a concurrence; a vote that dissented in part is coded by the side the justice took overall. Cases the justice sat out and equally divided cases are left out of the percentages. “Wrote” means authored an opinion. Source: Supreme Court Database (Spaeth et al.).

    Report a correction

    Scores: Martin, Andrew D. and Kevin M. Quinn. 2002. “Dynamic Ideal Point Estimation via Markov Chain Monte Carlo for the U.S. Supreme Court, 1953–1999.” Political Analysis 10:134–153, from mqscores.wustl.edu. Appointment data: Federal Judicial Center biographical directory. Biographies: Wikipedia, text abridged, under CC BY-SA 4.0. Portraits: public-domain images via Wikimedia Commons.