AZTEC — A Farmington man who pleaded no contest in the murder of his Alzheimer's disease-stricken father will be sentenced today.

Martin Casas-Rodriguez, 55, is facing up to nine years in prison as a condition of his plea agreement, which District Judge John Dean accepted April 10.

On April 7, 2012, Farmington police said Casas-Rodriguez shot and killed Eleuterio Casas, 90, at the family's home on Butler Avenue.

Casas died of a single gunshot wound to the chest, according to court documents.

Casas-Rodriguez allegedly called police and reported that he shot his father shortly after the shooting. According to court documents, he said he was scaring his father with a gun because the elderly man asked Casas-Rodriguez's wife for sex, and the gun accidentally discharged.

Police found the 9 mm handgun used to kill Casas at Casas-Rodriguez's home.

Casas-Rodriguez told police in an interview that Casas had suffered from Alzheimer's disease and dementia for several years. As his mental condition worsened, he started asking female family members and friends for sex, according to court documents.

Casas-Rodriguez has been in jail since the night of the shooting.

He was charged with an open count of murder and pleaded no contest to second-degree murder.

A second-degree murder conviction carries a maximum prison sentence of 15 years. Casas-Rodriguez's plea agreement states he won't serve more than nine years in prison.

Casas-Rodriguez's attorney, Arlon Stoker, said in court documents that his client has several family members who plan to speak on his behalf at today's sentencing.

Ryan Boetel can be reached at; 505-564-4644. Follow him on Twitter @rboetel.