How many Supreme Court justices will the President confirm?
I assess ~40% independent probability that the next President will confirm exactly one Supreme Court justice during the 2025–2029 term — most likely there will be one or two confirmations, with a nontrivial chance of none or multiple vacancies.
Analysis
**Stage 1 — Blind analysis (ignore market prices):**
- *Context & baseline:* No vacancy or announced retirement is reported in the provided materials, and there is no currently pending nomination tied to this market. That means any confirmation(s) depend on a future vacancy arising (retirement, death, resignation, elevation, or removal — removal is extremely rare). Historically, Supreme Court turnover in a four-year presidential term is low-to-moderate: many presidents see 0–2 confirmations in a single term, with occasional terms producing 3+. Given the absence of a known vacancy today (May 31, 2026) and the distribution of justice ages/tenures historically, the most reasonable single-point estimate is that the distribution of vacancies in the 2025–2029 term will center around 1 per term, with substantial probability mass at 0 and 2.
- *Quantitative intuition:* Modeling vacancies as a low-rate Poisson process calibrated to historical 4-year turnover (mean roughly 1.1–1.3 vacancies per term in recent decades) yields P(exactly 1) in the ~30–40% range. That approach folds in both retirements timed by political considerations and natural attrition. Given the current lack of announced retirements, I weight slightly toward the lower end of that range but still view exactly one confirmation as the single most likely outcome.
- *Other considerations (confirmation risk):* A vacancy does not necessarily produce a confirmed justice. Senate composition, filibuster rules, and political intensity matter. However, historically, when a President of the same partisan alignment as a controlling or cooperative Senate nominates, confirmation is likely; when the Senate opposes, nominations can be blocked. Because the provided context does not state the Senate's composition or any active blockade, I treat Senate confirmation probability conditional on a vacancy as middling-to-high but variable.
- *Independent probability conclusion:* Combining vacancy likelihood and conditional confirmation probability, I arrive at an independent (blind) estimate of ~40% that the next President will end up confirming exactly one justice during the 2025–2029 term.
**Stage 2 — Market calibration (compare to current market prices):**
- *Market snapshot:* The market places 44% on exactly 1, 35% on exactly 2, 20% on 0, 9% on 3, and 2% on 4. My independent 40% for '1' is close to the market; differences are modest.
- *Why the market might price 1 at 44% (slightly above my 40%):* Market participants appear to concentrate around a single-vacancy expectation. There may be more weight in the market on the idea that justices who are older or have signaled future retirement are likely to step down once the political environment is stable, producing exactly one vacancy. Heavy trading and volume (192,936 contracts) suggest many bettors have positional conviction.
- *Why I discount the market slightly:* I assign more probability to '2' (30%) than the market does (35%) and a bit more weight to '0' than an extreme pro-vacancy trader would. The reasons: 1) natural uncertainty about health/age patterns implies tail risk for multiple vacancies; 2) some justices delay retirement absent a favorable Senate, which increases the chance of zero vacancies; and 3) the confirmation process itself can yield blocked nominees or delayed confirmations that reduce the final count. These factors make me slightly less confident than the market that outcomes collapse so heavily on exactly one.
- *Possible market mispricings:* If the market is implicitly assuming high conditional confirmation probability once a vacancy occurs (close to 1), it may underweight scenarios where a nomination is significantly delayed or blocked. Conversely, if the market is over-weighting the chance of a single planned retirement based on leaked reporting not captured in the search results, it might be overconfident in 1. Overall the market is fairly aligned with my independent estimate; deviation is small and explicable by different assumptions about vacancy timing and Senate confirmation risk.
- *Implication for traders:* The market is tight around 1 vs 2. If you believe the President or sitting justices' private plans (or fragile health patterns) increase the chance of multiple vacancies, the market underprices the '2' and '3' buckets. If you believe justices will largely hold seat unless political conditions become favorable, the market underprices '0'.
Arguments
For
- Arguments for Yes 1: Historically, four‑year presidential terms commonly produce around one Supreme Court vacancy; absence of current announced vacancies does not preclude a single retirement or other vacancy over the remaining term.
- Arguments for Yes 2: Many justices time retirements to coincide with favorable political control; a President in office during 2025–2029 may get a single planned retirement and a cooperative Senate confirmation.
- Arguments for Yes 3: Conditional on a vacancy occurring, the probability of at least one confirmation is substantially higher than zero unless the Senate is overwhelmingly oppositional or chooses to leave a seat vacant for political reasons.
Against
- Argument against 1: No reported vacancies or announcements today implies a nontrivial chance that none will occur across the full term, especially if justices choose to remain until a more favorable partisan alignment or until advanced age precludes retirement.
- Argument against 2: Multiple vacancies (2 or more) are possible if several older justices face health issues or choose to retire in short succession; that would reduce the share of probability that exactly one confirmation occurs.
- Argument against 3: Even with one vacancy, political dynamics could produce a blocked or significantly delayed nomination such that no confirmation is completed during the term—turning an expected '1' into '0'.
Key drivers
- Timing and occurrence of a Supreme Court vacancy (retirement, death, resignation, elevation).
- Senate composition and willingness to confirm nominees during 2025–2029.
- Health, age, and precedent-based retirement incentives of sitting justices.
- Political incentives for a justice to time retirement (alignment with President and Senate).
Risk factors
- Sudden health events or unexpected resignations that create multiple vacancies in short order.
- A polarized Senate that effectively blocks nominees—turning vacancies into confirmed-zero outcomes.
- Unforeseen legal or political reforms affecting nomination/confirmation rules.
- Information leaks (private retirement plans) or late announcements that materially shift probabilities.
Scenarios
Best case
Exactly one vacancy occurs midterm (retirement or other departure) and the President nominates a consensus candidate who is confirmed by the Senate before January 20, 2029 — this is the scenario underpinning the ~40% estimate for '1'.
Most likely
One or two confirmations: the single most probable exact outcome is 1 (≈40%), but combined probability of 1 or 2 confirmations is high (~70%), reflecting historical turnover and the possibility of multiple retirements or successive vacancies.
Worst case
Either no vacancies occur (all sitting justices remain through 2029) or multiple vacancies occur and the President ends up confirming 2–4 justices; the most disruptive worst-case for a single-confirmation prediction is two or more near-simultaneous vacancies producing multiple confirmations.
Outcomes
| Outcome | AI | MKT |
|---|---|---|
| 1 | 40% | 44% |
| 2 | 30% | 35% |
| 0 | 15% | 20% |
| 3 | 10% | 9% |
| 4 | 5% | 2% |
More from this day
- economyPolymarket3mo
How high will inflation get in 2026?
AI25%MKT98%Edge-73HypedI assess a substantially below-market probability that headline CPI will exceed 4% in any month of 2026; the baseline is continued disinflation with meaningful upside-tail risks from energy, supply shocks, or sudden demand acceleration.
- PoliticsKalshi18y
Which G7 leader will leave next?
AI18%MKT77%Edge-59HypedIndependent view: the UK Prime Minister is unlikely to be the next G7 leader to leave — other leaders (notably Emmanuel Macron and Italy's Giorgia Meloni) carry higher short-to-medium term exit risk. I assign the UK PM a substantially lower probability than the current market.
- FinancialsKalshi13y
Will OpenAI or Anthropic IPO first?
AI70%MKT29%Edge+41Hidden GemI assess ~70% chance that OpenAI will IPO before Anthropic. OpenAI shows clearer preparatory work, stronger near-term monetization paths, and investor incentives to pursue a public listing sooner than Anthropic.