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STEPHENVILLE (CBSDFW.COM/AP) — An attorney for the former Marine found guilty in the shooting deaths of “American Sniper” author Chris Kyle and his friend Chad Littlefield has filed an appeal.

Eddie Ray Routh was convicted of capital murder in the 2013 shooting deaths of Kyle and Chad Littlefield at the Rough Creek Lodge shooting range, about 50 miles southwest of Fort Worth, after jurors rejected his insanity defense.

Prosecutors hadn’t sought the death penalty, so Routh was sentenced to life in prison without parole.

Routh’s attorneys said after the February 24 verdict they would appeal. J. Warren St. John, one of Routh’s attorneys, said the notice of appeal was filed Tuesday. St. John also filed a motion for a new trial, arguing the conviction and sentence were contrary to law and evidence.

The case drew extra attention due to the film based on Kyle’s memoir.

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