PINEVILLE, Mo. — A brief in support of an appeal for Sheena Eastburn, a McDonald County woman who at age 17 was charged with first-degree murder and then in 1995 given life in prison with no chance for parole, will be filed next month with the Missouri Supreme Court.

Eastburn’s attorney, Kent Gipson, of Kansas City, said the appeal is bypassing the appellate court and going directly to the Supreme Court because it involves the validity of a statute under the Missouri Constitution.

Gipson said he hopes to have the case docketed for oral arguments before the Missouri Supreme Court in March or April. A decision from the court would be expected 60 to 90 days after that.

Gipson said the brief will spell out “what the remedy should be and resentencing should be, and whether it is retroactive.’’

On June 25, the U.S. Supreme Court found in Miller v. Alabama that the Eighth Amendment forbids sentencing that mandates life in prison without the possibility for parole for juvenile homicide offenders. A Missouri statute and similar statutes in other states that permitted that sentencing were found to be unconstitutional.

After the ruling, Nanci Gonder, press secretary for Missouri Attorney General Chris Koster, said, “The attorney general’s office is taking the position that the decision does not apply retroactively.’’

Gipson said a defendant in a companion case to Miller v. Alabama in Arkansas “had already passed the appeal stage. If the decision was not retroactive, the court would not have ruled in his favor.’’

Gipson said he will argue that Eastburn’s conviction of first-degree murder should be vacated and that she should be found guilty of second-degree murder. Such a ruling could open the door for Eastburn, now 36 and a prisoner at Chillicothe Correctional Center, to be sentenced to life in prison with the possibility of parole.

The appeal was filed after McDonald County Circuit Judge Tim Perigo issued a ruling that denied a motion for a new trial that was based on claims of ineffective counsel during Eastburn’s 1995 trial.

Citing a technicality, Perigo said his ruling “was procedural in nature because the Supreme Court ruled last year that it is the court’s duty to follow the rules of the Supreme Court. Those rules say a court shall not entertain a successive motion.

“This was a successive motion in that the original motion for a new trial was appealed in 1997 and denied. Any motion after that would be successive. I shall not entertain a successive motion in this case.”

Gipson said Perigo was “just delaying the remedy to which she is entitled. Her sentence and conviction of first-degree murder at age 17 with no possibility of parole will eventually be overturned.”

Eastburn was 17 when her ex-husband, Tim Eastburn, was killed in 1992. She was sentenced to life in prison without the possibility of parole for her part in the death.

If the appeal before the Missouri Supreme Court is upheld, the matter would revert to Perigo, who then would be tasked with deciding whether a new trial is warranted or whether Eastburn’s conviction on the first-degree murder charge should be overturned because of the Supreme Court ruling.

With regard to the claim of ineffectiveness of counsel in 1995, Gipson said the jury in her trial did not hear that Eastburn allegedly was raped two times by a jailer while being held in the McDonald County Jail. The jury also was not told that Eastburn allegedly became pregnant while in jail and that her pregnancy was aborted.

The jailer, Terrie Zornes, 47, of Pineville, was charged in the Eastburn rape case after new evidence came to light last year. In a plea bargain in September, he obtained dismissal of the rape charge involving Eastburn in exchange for pleading guilty to making sexual advances toward a 14-year-old girl in 2010. He is serving four years in a state prison.

The motion for a new trial, citing ineffective counsel, was filed in September 2010. The court held evidentiary hearings on one day last year and another earlier this year in which witnesses gave conflicting testimony about the circumstances of Eastburn’s 1995 trial in McDonald County.

Gipson contends that Eastburn was “under the substantial domination” of two other defendants who participated in the murder of Tim Eastburn, including the gunman who had stolen Eastburn’s rifle and used it to kill him.

Prosecutors alleged that Eastburn lured her ex-husband into the kitchen of his home near Rocky Comfort on Nov. 19, 1992, setting him up to be shot by Terry Banks and Matthew Myers. After a plea bargain, Myers was sentenced to 67 years on a reduced charge of second-degree murder. Banks was convicted of first-degree murder and was sentenced to life without parole.

Eastburn testified that she had “no understanding of what was happening in court” at the time of her trial.