MINNEAPOLIS (AP) — A federal appeals court has upheld a Minnesota woman’s 15-year sentence for threatening to kill two law enforcement officers.

Kim Rolene Hutterer pleaded guilty in July 2011 to counts stemming from threats she made to a federal prisons corrections officer, and to FBI Special Agent Dean Scheidler, who arrested her decades earlier for making bomb threats against an airline.

Court documents show Hutterer sent graphic threats to Scheidler for years. After pleading guilty, she continued to write letters to Scheidler, his wife and other authorities.

Hutterer’s attorneys argued her 15-year sentence was unreasonable.

But a three-judge panel of appeals court judges found Tuesday the higher sentence was proper. Among other things, they say since Hutterer continued to send threatening letters after pleading guilty, she did not accept responsibility.

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