
John G. Roberts, Jr.
Chief Justice of the U.S. Supreme Court · Appointed by George W. Bush (Republican)
Took seat Sep 29, 2005 · Confirmed 78–22 on Sep 29, 2005 (Senate roll call #245, 109th Congress) · Born 1955, NY
supremecourt.gov biography · supremecourt.gov list of justices · FJC biography · Wikipedia · Portrait: Wikimedia Commons
Left–right score over time
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The colored line is John G. Roberts, Jr.'s Martin-Quinn score each term (shaded band = the range the estimate is 95% likely to fall in); faint lines are the other current justices. Left = more liberal, right = more conservative. This is a different scale from the Congress score (roughly −4 to +4) and can't be compared with lawmakers' scores.
By term
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| Term | MQ score | 95% range | Cases | In majority | Dissented |
|---|---|---|---|---|---|
| 2025 | No score yet | 66 | 95% | 5% | |
| 2024 | +0.33 | -0.20 to +0.88 | 63 | 97% | 3% |
| 2023 | +0.43 | -0.02 to +0.92 | 59 | 97% | 3% |
| 2022 | +0.42 | -0.04 to +0.90 | 58 | 93% | 7% |
| 2021 | +0.55 | +0.13 to +1.00 | 64 | 94% | 6% |
| 2020 | +0.52 | +0.08 to +0.96 | 65 | 94% | 6% |
| 2019 | +0.34 | -0.09 to +0.77 | 62 | 97% | 3% |
| 2018 | +0.41 | -0.01 to +0.84 | 73 | 85% | 15% |
| 2017 | +0.40 | +0.01 to +0.83 | 75 | 93% | 7% |
| 2016 | +0.35 | -0.11 to +0.82 | 68 | 94% | 6% |
| 2015 | +0.33 | -0.12 to +0.79 | 77 | 91% | 9% |
| 2014 | +0.59 | +0.15 to +1.03 | 74 | 80% | 20% |
| 2013 | +0.80 | +0.30 to +1.33 | 75 | 92% | 8% |
| 2012 | +1.11 | +0.64 to +1.58 | 79 | 86% | 14% |
| 2011 | +1.20 | +0.71 to +1.72 | 76 | 91% | 9% |
| 2010 | +1.40 | +0.90 to +1.95 | 81 | 91% | 9% |
| 2009 | +1.40 | +0.87 to +1.95 | 93 | 90% | 10% |
| 2008 | +1.50 | +1.00 to +2.03 | 83 | 82% | 18% |
| 2007 | +1.41 | +0.89 to +1.95 | 71 | 90% | 10% |
| 2006 | +1.43 | +0.90 to +2.02 | 72 | 89% | 11% |
| 2005 | +1.39 | +0.76 to +2.08 | 82 | 93% | 7% |
Since joining the Court: in the majority in 91% and dissenting in 9% of 1516 cases (case data from 1991).
Recent votes (latest 60 of 1539)
Case votes: Supreme Court Database (SCDB_2026_01, covering terms 1946-2025; this site uses 1985–2025) plus the Oyez API for newer terms (October Term 2026: Oyez lists 31 cases, 0 decided so far). Ideology: Martin-Quinn scores through the 2024 term.