A more thorough explanation:

Recuse means that a judge decides not to take part in deciding a case that they would normally help decide. This is done to ensure that the judge's decision is fair and unbiased.

There are two situations where judges are required to recuse themselves:

• When the judge has a financial interest in the outcome of the case
• When there is a strong possibility that the judge's decision will be biased

Even if the judge is not actually biased, the high probability of bias can damage the integrity of the judicial system. Any party in a lawsuit can request that a judge recuse themselves.

For example, in the case of Caperton v. A. T. Massey Coal Co., one party asked a judge to recuse himself because the other party's CEO spent over $3 million getting the judge elected. Even though there was no evidence that the judge was biased, the Supreme Court still held that he had to recuse himself to ensure a fair trial.