HUNTSVILLE — The capital murder trial in the death of correctional officer Susan Canfield has been delayed for another day as attorneys from the state and defense await the ruling by the 10th Court of Appeals about the appropriateness of jury instructions.

Walker County District Attorney David Weeks and special prosecutor Jane Starnes are challenging the “fairness” of 278th District Judge Ken Keeling’s instructions to the jury in the trial of Texas prison inmate John Ray Falk Jr., claiming the wording made it more difficult for the prosecution to prove that Falk —who escaped with Jerry Duane Martin from the Wynne Unit in Huntsville five years ago — is responsible as a co-conspirator for Canfield’s death.

Trial officials made oral arguments before the Court of Appeals on Monday morning at the McLennan County Courthouse in Waco. Falk’s trial, which began Nov. 26 in Bryan, has been on hold since Dec. 3 after Weeks filed a writ of mandamus asking the high court to halt the trial court’s proceedings until it could rule on the state’s objections to the jury’s instructions. Weeks filed his writ before closing arguments began in the trial.

Canfield, 59, an officer supervising inmates in the field while mounted on horseback, died Sept. 24, 2007, trying to prevent the inmates’ escape; her horse was struck by a truck Martin stole from the City of Huntsville Service Center, which caused her to sustain fatal injuries when she fell from the horse. Martin was convicted of capital murder for his role in Canfield’s death in 2009. Falk, who was a passenger in the truck while also trying to escape, faces lethal injection if he is found guilty.

The instructions — which in capital cases typically include four questions the jurors must answer to determine Falk’s guilt — in this case say that Falk should have anticipated that Martin would murder Canfield by striking her horse with a vehicle. The state is asking the Court of Appeals to amend the instructions, arguing there are no previous cases in which the prosecution had to prove the defendant anticipated the specific manner and means in which a murder was committed.

Co-defense attorney Lane Thibodeaux and Rick Metzel, an Austin lawyer representing Keeling, say that the instructions were written that way because of the language of the state’s indictment of Falk. Thibodeaux also contends that there are not any previous cases that say a judge cannot include manner and means in the jury instructions.

Falk’s trial is scheduled to resume Monday at the Brazos County Courthouse, pending a ruling by the Court of the Appeals on Weeks’ writ of mandamus.