Announcing the Release of the 123rd Indiana General Assembly and the 102nd Michigan Legislature State Legislative Effectiveness Scores (SLES)
The Center for Effective Lawmaking (CEL) is proud to announce the release of our State Legislative Effectiveness Scores (SLES) for the 123rd Indiana General Assembly and the 102nd Michigan Legislature legislative sessions (2023–2024). This initiative is part of our broader effort to measure the lawmaking effectiveness of individual legislators in all 99 state legislative chambers in the United States.
These scores capture lawmaking effectiveness by tracking the number of bills legislators sponsor, how far those bills advance through the legislative process, and the substantive significance of the proposals.
With the release of Indiana and Michigan, our state-level data initiative continues to grow—building on earlier reports from Montana and Georgia. Additional states will be added in the coming months as we work toward full national coverage.
Highlights from the Michigan and Indiana SLES (2023–2024)
- Top Performers: We identify the top 10 most effective lawmakers from each party in both the Illinois Assembly and Senate, including legislators who have consistently ranked highly across multiple legislative sessions.
- Above Expectations: We highlight members who earned our prestigious Above Expectations designation for lawmaking effectiveness, including both experienced legislators with sustained records and first-term lawmakers who quickly distinguished themselves among their peers.
- Majority Party Advantage: Consistent with CEL research, majority-party legislators were generally more effective lawmakers, reflecting structural advantages such as agenda-setting power and committee leadership.
- Indiana Findings: In terms of broader patterns, partisanship continues to be strongly associated with lawmaking success in Indiana. While the SLES of minority-party lawmakers across the country on the whole averages about 0.6, the scores for minority-party members in the Indiana House of Representatives have been lower still, averaging around 0.4 in the House and only slightly higher in the Senate. While Democrats are disadvantaged at lawmaking, they have not been completely shut out of the legislative process, although nearly so. For example, in the 2023-2024 term, Democratic legislators introduced 24 bills that became law. In contrast, the number of laws sponsored by Republicans in that term totaled 399. This approximately 15:1 ratio is significantly out of proportion to the number of seats the parties hold in the chambers, and well beyond what is seen in most legislatures across the country.
- Michigan Findings: In terms of broader patterns, similar to what we observed in Indiana, partisanship is strongly associated with lawmaking success in Michigan. While the SLES of minority-party lawmakers across the country on the whole averages about 0.6, the scores for minority-party members (Republicans) in the Michigan State Legislature averaged only half that level, sitting about 0.3 in the 2023-24 term. A good portion of that divide comes from Democrats controlling both chambers and the governorship for the first time in decades. Over the prior decade, Republicans held the majority in both chambers, leading to a large pent-up set of proposals from Democrats. For example, in the decade from 2013-2022, only 547 bills proposed by Democrats became law, about one-sixth of the number of Republican bills becoming law. But when in the majority, Democrats in 2023-24 were able to advance 534 of their bills to law, nearly as many as in the entire prior decade. This left little time or room for Republican proposals, only 62 of which became law in the 2023-24 term.
You can explore the full report and detailed findings below:
- Read the Indiana Report
- Read the Michigan Report
- View the SLES Scores
