Kansas City, Mo. ? A former Westar Energy Inc. executive is trying to invalidate an appeals court decision that could send him back to prison.

Attorneys for David Wittig, the Topeka-based utility’s former chief executive officer, this week asked the 10th U.S. Circuit Court of Appeals to rehear his appeal of a 24-month prison sentence for bank fraud.

A three-judge panel of the court last month upheld the sentence, which was imposed last year by U.S. District Judge Julie Robinson.

But attorneys for Wittig said the panel simply “rubber-stamped” Robinson’s decision and want all 12 appellate judges to reconsider the case.

The court already has thrown out two previous sentences of 51 and 60 months against Wittig as too harsh and had recommended Robinson sentence him to no more than six months. But she ignored that recommendation, saying a longer sentence was warranted because of the seriousness of the crime and because Wittig’s co-defendant was sentenced to five years in prison even though they were convicted of similar crimes.