First, when a legislator knows she will never again face reelection, the deterrent effect of the electoral sanction disappears, leaving fewer disincentives for a politician to engage in corruption. This paper found that the corruption was twice as prevalent among Brazilian mayors in their final term, compared to similarly situated mayors who could run for reelection. (A similar study found that increasing the maximum number of terms for Brazilian mayors from two to three was more effective in reducing corruption than increasing the mayors salary.) This result is actually quite intuitive. Indeed, if one believes that certain politicians are seeking office for personal enrichment, then when there is a definite end date for that persons political career, they are likely to try to cash in before it is too late. Even a study arguing that term limits have positive effects on governance suggests that removing the possibility of reelection offsets term limits demand-reducing effect. This suggests that if states impose term limits, it will be important to balance the desire to keep entrenched legislators from becoming corrupt against the potential risk that otherwise upstanding legislators feel more comfortable engaging in corruption because they will never again face reelection.
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Third, to the extent one is concerned that campaign finance gives special interests outsize power to influence policy, replacing long-serving members with new members might actually increase special interest influence. For example, if a long-serving member is electorally safe, it will be more difficult for private interests to influence her. If term limits force the incumbent legislator to retire, her replacement is unlikely to have the same ability to act counter to special interests without increased political risk. Indeed, the current system by which parties select candidates suggests that the very donors who could not capture the hypothetical long-serving legislator might be the people who choose the candidate who replaces her. Consistent with this, some research has found a correlation between increased campaign contributions and the adoption of term limits in Ohio. In short, term limits probably risk enhancing special interest powers that may breed the seeds of corruption.