Federalism: how each Justice has voted
National supremacy, state sovereignty and the balance between federal and state power. 419 cases since 1946 in the Supreme Court Database (plus OT2025 from our records). The chart shows each sitting Justice's share of votes on the liberal side over a rolling three-term window; gaps mean too few votes.
- Possible shift: Sonia Sotomayor voted more liberally relative to the Court in OT2017–OT2025 (lean +0.22, 18 votes) than in OT2009–OT2016 (lean -0.11, 27 votes); p = 0.0338, q = 0.4056 after correcting for multiple tests — not significant after that correction.
first vs second half of tenure, relative lean, permutation test; shift if Benjamini-Hochberg q < 0.1 across all tests; >= 12 votes in each half, >= 6 terms. "Lean" compares each vote with the Court's majority in the same case (+ more liberal, − more conservative), so it is not driven by which cases the Court chose to hear. Justices with short tenures or few votes on an issue are not tested.
| Justice | Votes | Liberal side | Lean vs Court | Opinions written |
|---|---|---|---|---|
| Elena Kagan | 38 | 66% | +0.03 | 6 |
| Sonia Sotomayor | 45 | 64% | +0.02 | 10 |
| John G. Roberts Jr. | 59 | 64% | +0.02 | 9 |
| Samuel A. Alito Jr. | 56 | 57% | -0.04 | 13 |
| Brett M. Kavanaugh | 17 | 41% | -0.06 | 3 |
| Clarence Thomas | 137 | 46% | -0.11 | 56 |
| Neil M. Gorsuch | 18 | 33% | -0.11 | 3 |
| Amy Coney Barrett | 8 | 38% | -0.25 | 1 |
| Ketanji Brown Jackson | 4 | 50% | -0.25 | 1 |
| Case | Jr. | Thomas | Jr. | Sotomayor | Kagan | Gorsuch | Kavanaugh | Barrett | Jackson |
|---|---|---|---|---|---|---|---|---|---|
| National Federation of Independent Business, et al., Petitioners v. Kathleen Sebelius, Secretary of Health and Human Ser (OT2011, liberal outcome) | L✎ | C✎ | C✎ | L | L | — | — | — | — |
L = liberal side, C = conservative side (Supreme Court Database coding); ✎ = wrote an opinion; — = not on the Court.
Source: Supreme Court Database (Spaeth et al.) votes through OT2024; OT2025 from our decision records. Direction coding follows the Supreme Court Database, which classifies, e.g., pro-defendant, pro-civil-liberties and pro-regulation outcomes as liberal; it is a convention, not a judgment.