Supreme Court mail ballot bar consensus hardens at 76 percent

Name: Supreme Court mail ballot bar consensus hardens at 76 percent
Creator: ClearMarket
Published: 2026-06-18T18:06:09.000Z
License: https://creativecommons.org/licenses/by/4.0/

Kalshi 76%

record: CMSIG2026061807 | category: momentum-repricing | target: CM-EVT-8NWCS8ZRW8 | published: 2026-06-18

4-bullet brief | narrative

Kalshi prices 76% on the Supreme Court barring counting of mail ballots received after Election Day.
The Boston ruling narrowing challenges removes a lower-court obstacle and is consistent with Kalshi's elevated 76% probability.
The 2026 midterms proceeding as scheduled is priced at 94% on Polymarket (CM-EVT-99YJSN2LN7), so a ballot-rule fight occurs against a high-certainty election backdrop.
Resolves via Supreme Court decision; the narrowing of lower-court suits increases the probability this reaches SCOTUS as the sole arbiter.

atomic briefs | structured for retrieval

[01] news_event

significance

surfaced in the daily Exa news-cycle scan; mechanically matched to an active kalshi market

story: A federal judge in Boston narrowed lawsuits challenging Trump's executive order on mail-in voting, limiting challenges to the order's effect on November's midterms.exa_search → devdiscourse.com · as_of 2026-06-19T12:03:18+00:00
publisher: devdiscourse.com
published_at: 2026-06-18T18:06:09.000Z
source_url: https://www.devdiscourse.com/article/politics/3937105-us-judge-narrows-lawsuits-challenging-trumps-executive-order-restricting-mail-in-voting

[02] pm_response

interp: Kalshi resolves via Supreme Court ruling; the Boston court's narrowing decision reduces alternative resolution paths and concentrates the question at the highest court.llm_judge_cm_signal_v1

evaluation

News-cycle wires publish on coverage, not editorial selection — the day’s top stories matched to the prediction markets pricing them, so nothing is cherry-picked.

judge_engine: none — deterministic news-cycle scan
judge_verdict: auto_published
judge_confidence: n/a — no judge gate (deterministic publishing)
prompt_template: news_cycle_v1 github · auditable
match_method: entity_slug_match (mechanical)

citation graph

Every wire traces back to the ClearMarket event it is built on, and out to each venue’s own market page — so any figure here can be verified at its source.

internal

cm_event: /events/kxwatsonrnc/

external

venue_a: https://kalshi.com/markets/KXWATSONRNC

programmatic access · four surfaces, same payload

AI grounded search reads embedded JSON-LD in HTML. Developers query REST. Agentic AI clients (Claude Desktop, Cursor) call MCP tools. AI crawlers index via /llms.txt. Same canonical record at every surface.

HTML	browsers, AI grounded search, crawlers (contains embedded JSON-LD `@type: Dataset`)	`https://clearmarket.fyi/signals/scotus-bars-late-mail-ballots-by-nov-2026-kalshi-76-2026-06-18/`
JSON	REST API for developers	`https://clearmarket.fyi/signals/scotus-bars-late-mail-ballots-by-nov-2026-kalshi-76-2026-06-18.json`
MCP	agentic AI tool call (Claude Desktop, Cursor, Continue)	`clearmarket.get_signal("scotus-bars-late-mail-ballots-by-nov-2026-kalshi-76-2026-06-18")`
AGENT	AI crawler discovery index	`/llms.txt`

 PM data: platform APIs (hourly refresh). News context: retrieved with source citations. Editorial judgment: LLM judge with prompt template versioned per wire type. Per-claim provenance inline above; full per-field provenance map at the JSON endpoint under field_provenance.
  raw JSON record · same payload returned by REST endpoint
 {
  "$schema": "https://clearmarket.fyi/schema/signal/v1.json",
  "provenance_version": "0.2.0",
  "record_id": "CMSIG2026061807",
  "published_at": "2026-06-18T18:06:09.000Z",
  "detection": "news_cycle",
  "category_tag": "MOMENTUM_REPRICING",
  "secondary_tags": [],
  "pre_news_classification": "concurrent",
  "target_event_id": "CM-EVT-8NWCS8ZRW8",
  "target_event_slug": "kxwatsonrnc",
  "event_question": "Will the Supreme Court of the United States bar the counting of mail ballots received after Election Day?",
  "bullets": [
    "Kalshi prices 76% on the Supreme Court barring counting of mail ballots received after Election Day.",
    "The Boston ruling narrowing challenges removes a lower-court obstacle and is consistent with Kalshi's elevated 76% probability.",
    "The 2026 midterms proceeding as scheduled is priced at 94% on Polymarket (CM-EVT-99YJSN2LN7), so a ballot-rule fight occurs against a high-certainty election backdrop.",
    "Resolves via Supreme Court decision; the narrowing of lower-court suits increases the probability this reaches SCOTUS as the sole arbiter."
  ],
  "atomic_claims": [
    {
      "type": "news_event",
      "field_provenance": {
        "story": {
          "tier": "mediated",
          "method": "exa_search",
          "source": "devdiscourse.com",
          "source_url": "https://www.devdiscourse.com/article/politics/3937105-us-judge-narrows-lawsuits-challenging-trumps-executive-order-restricting-mail-in-voting",
          "retrieved_at": "2026-06-19T12:03:18+00:00"
        }
      },
      "significance": {
        "threshold": 5,
        "threshold_unit": "rank",
        "passed": true,
        "reason": "surfaced in the daily Exa news-cycle scan; mechanically matched to an active kalshi market"
      },
      "story": "A federal judge in Boston narrowed lawsuits challenging Trump's executive order on mail-in voting, limiting challenges to the order's effect on November's midterms.",
      "publisher": "devdiscourse.com",
      "published_at": "2026-06-18T18:06:09.000Z",
      "source_url": "https://www.devdiscourse.com/article/politics/3937105-us-judge-narrows-lawsuits-challenging-trumps-executive-order-restricting-mail-in-voting"
    },
    {
      "type": "pm_response",
      "field_provenance": {
        "notes": {
          "tier": "editorial",
          "method": "llm_judge_cm_signal_v1"
        }
      },
      "notes": "Kalshi resolves via Supreme Court ruling; the Boston court's narrowing decision reduces alternative resolution paths and concentrates the question at the highest court."
    }
  ],
  "evaluation": {
    "judge_engine": "none — deterministic news-cycle scan",
    "judge_verdict": "auto_published",
    "judge_confidence": null,
    "prompt_template": "news_cycle_v1"
  },
  "citations": {
    "internal": {
      "cm_event": "/events/kxwatsonrnc/",
      "related": []
    },
    "external": {
      "venue_a": "https://kalshi.com/markets/KXWATSONRNC",
      "venue_b": null,
      "benchmark": null
    }
  },
  "sources": [
    {
      "label": "devdiscourse.com: US judge narrows lawsuits challenging Trump's executive order restrict",
      "url": "https://www.devdiscourse.com/article/politics/3937105-us-judge-narrows-lawsuits-challenging-trumps-executive-order-restricting-mail-in-voting",
      "published_at": "2026-06-18T18:06:09.000Z",
      "retrieved_at": "2026-06-19T12:03:18+00:00"
    }
  ],
  "field_provenance": {
    "pm_data": "kalshi_api",
    "news_context": "exa_search",
    "editorial_judgment": "cm_signal_llm_judge"
  }
}
 
   PROVENANCE PROTOCOL v0.2 · [direct] venue api · [mediated] grounded web fetch + source url · [derived] computed from listed inputs · [editorial] versioned llm judgment · full spec /schema/provenance/v1

record CMSIG2026061807 published 2026-06-18T18:06:09.000Z signature sha256-6182811d09b… ← underlying event all signals →