Jurors in the kidnapping trial of a German-born man calling himself Clark Rockefeller have asked the judge for more explanation on the insanity defense.

The jurors sent a written question to Judge Frank Gaziano Wednesday asking exactly what prosecutors must prove to show Rockefeller was sane when he kidnapped his 7-year-old daughter in Boston last July.

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Gaziano told them the state must prove Rockefeller knew both that what he was doing was criminal and that it was morally wrong.

Defense lawyers say Rockefeller, whose real name is Christian Karl Gerhartsreiter, was legally insane when he fled to Baltimore with his daughter.

Prosecutors call his insanity claim "preposterous" and say he planned the kidnapping for months.

• Partial List of Witnesses at the 'Clark Rockefeller' Trial

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