The man considered the Supreme Court's swing vote is questioning the way some senators may grill the woman nominated to share the bench with him.
In a speech in West Palm Beach on Friday, Justice Anthony Kennedy said lawmakers should not try to figure out how high court nominee Elena Kagan would rule on specific questions.
He said they should instead look at whether her temperament, commitment and character make her suitable for the job.
Kennedy declined to offer Kagan any advice. He joked that if you ask him what makes a good judge, "you're going to get an autobiography."
Kagan, the nation's solicitor general, was tapped by President Barack Obama to succeed retiring Justice John Paul Stevens.
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