Passage Likelihood Methodology

How we calculate the probability that a bill will become law

Overview

Our passage likelihood score combines rule-based analysis of legislative data with AI-powered assessment of political factors. The final score (0-100%) represents our estimate of whether a bill will pass both chambers and be signed into law during the current session.

Note: These scores are estimates based on historical patterns and current indicators. Legislative outcomes depend on many unpredictable factors including negotiations, amendments, and political dynamics that cannot be fully modeled.

Factor Breakdown

Positive Factors

Session Timing

+0 to +15

Bills introduced earlier in a session have more time to move through the legislative process.

• Early session (Jan-Mar): +13 to +15 points
• Mid session (Apr-May): +8 to +12 points
• Late session (Jun): +3 to +7 points
• End of session: +0 to +2 points

Sponsor Strength

+0 to +15

The political influence and position of the bill's primary sponsor significantly impacts passage odds.

• Committee Chair sponsor: +4 bonus (chairs can move bills through their committees)
• Rules bill: +6 points (indicates leadership support)
• Budget bill: +5 points (part of must-pass budget process)
• Assembly bills: 10+ co-sponsors = +2, 25+ = +4, 50+ = +6
• Senate bills: 5+ co-sponsors = +2, 15+ = +4, 30+ = +6
• Multi-sponsors (bipartisan): +1 to +3 based on count

Priority Alignment

+0 to +10AI

AI assessment of how well the bill aligns with current legislative priorities and political momentum.

• Evaluates alignment with majority party agenda
• Considers timing relative to current events
• Assesses political feasibility given current dynamics

Bicameral Support

+0 to +10AI

Whether the bill has a companion bill in the other chamber and its status.

• Same-as bill exists: indicates coordinated effort
• Same-as bill advancing: strong positive signal
• No same-as: bill must find Senate/Assembly partner later

Governor Support

+0 to +10AI

AI assessment of whether the Governor is likely to sign the bill based on stated positions and past actions.

• Considers Governor's public statements
• Reviews past vetoes of similar legislation
• Evaluates alignment with executive priorities

External Influence

-10 to +10AI

AI assessment of stakeholder support and opposition, particularly from influential groups.

• Public unions and labor support: strong positive signal
• Business coalition support: positive signal
• Organized opposition from key stakeholders: negative signal
• Neutral/no major stakeholder interest: minimal impact

Committee Path

-15 to +15

Progress through key committees signals momentum and institutional support.

• Currently in Rules: +8 (near floor consideration)
• Currently in Finance/Ways & Means: +6 (fiscal review stage)
• Currently in Codes: +4 (legal review stage)
• Passed through Rules: +10 (strong momentum)
• Passed through Finance/Ways & Means: +8
• Passed through Codes: +6
• Stuck in initial committee: -5 to -15 depending on duration

Risk Factors

Fiscal Impact

-10 to 0AI

Bills with significant budget implications face additional scrutiny and resistance.

• High fiscal impact: -10 (requires budget accommodation)
• Moderate fiscal impact: -5 (may face fiscal committee delays)
• Minimal/no fiscal impact: 0 (easier path)

Opposition Risk

-10 to 0AI

AI assessment of organized opposition and political controversy.

• Strong organized opposition: -10
• Moderate opposition or controversy: -5
• Minimal opposition: 0
• Considers industry lobbying, advocacy groups, partisan dynamics

Chamber-Aware Scoring

The Senate (63 members) and Assembly (150 members) have different dynamics for building support:

Senate Bills

• 5+ co-sponsors = meaningful support
• 15+ co-sponsors = strong support
• 30+ co-sponsors = near-majority coalition
• <5 co-sponsors = limited traction penalty

Assembly Bills

• 10+ co-sponsors = meaningful support
• 25+ co-sponsors = strong support
• 50+ co-sponsors = broad coalition
• <10 co-sponsors = limited traction penalty

Committee Chair Sponsorship

When a bill's primary sponsor chairs a legislative committee, it receives a +4 point boost to the Sponsor Strength factor. This reflects the institutional power committee chairs hold:

• Chairs control their committee's agenda and can prioritize their own bills
• Chair sponsorship signals serious legislative intent
• Chairs often have strong relationships with leadership
• Bills sponsored by chairs are less likely to die in committee

Committee chair status is indicated with a ⭐ badge on bill pages.

Key Committee Progression

Certain committees serve as gatekeepers in the legislative process. Being referred to or passing through these committees is a positive signal, not a penalty:

Rules Committee

Final stop before floor consideration. Bills in Rules are close to a vote. Passing Rules indicates leadership has approved the bill for floor action.

Finance / Ways & Means

Reviews bills with fiscal implications. Being here means the bill has substantive support and is being seriously evaluated for budget impact.

Codes Committee

Reviews bills affecting criminal law and procedures. Referral here indicates the bill has advanced past initial subject-matter committee review.

AI-Powered Analysis

Several factors are assessed using GPT-4.1-mini, which analyzes the bill text along with contextual information about the current legislative environment:

AI-Assessed Factors

• Priority Alignment: Does this match current legislative priorities?
• Bicameral Support: Is there coordinated effort across chambers?
• Governor Support: Will the Governor sign this?
• External Influence: What stakeholders support or oppose this?
• Fiscal Impact: What are the budget implications?
• Opposition Risk: Is there organized resistance?

AI assessments are cached and refreshed periodically. Click "Refresh AI" on any bill page to get an updated analysis.

Score Calculation

Raw Score = 
  Session Timing (0-15)
  + Sponsor Strength (0-15)
  + Priority Alignment (0-10)      [AI]
  + Bicameral Support (0-10)       [AI]
  + Governor Support (0-10)        [AI]
  + External Influence (-10 to +10) [AI]
  + Committee Path (-15 to +15)
  - Fiscal Impact (0-10)           [AI]
  - Opposition Risk (0-10)         [AI]

Final Score = max(0, min(100, Raw Score))

Maximum possible: ~95 points. Most bills score between 10-40%.