Prosecutors are alleging that Delphi, Indiana, double murder suspect Richard Allen, while in custody, confessed five or six times to the killings.

       Defense attorneys didn't dispute the allegation in a Thursday hearing, but argued the confessions were unreliable because of Allen's deteriorating mental and physical health.

       Richard Allen was charged in 2022 with the murders of Abby Williams, 13, and Libby German, 14.

       Indiana State Police

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       Judge Fran Gull is considering the defense's request to move Allen to a different facility.

       Allen was arrested in October 2022 and charged with two counts of murder for the deaths of Abby Williams, 13, and Libby German, 14. The best friends were enjoying a day off from school when they were killed on a Delphi hiking trail in February 2017.

       Photos of Abby Williams, left, and Libby German, right, at police headquarters in Delphi, Ind.

       Lindsey Jacobson/ABC News

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       Allen, a Delphi resident, has pleaded not guilty.

       Allen's trial has been scheduled for January 2024.