Jury selection began Thursday for the high-profile murder case along the southern border involving 75-year-old George Kelly, the man accused of killing a Mexican migrant on his property.
Kelly is facing second-degree murder and aggravated assault charges in the fatal shooting of 48-year-old Gabriel Cuen-Buitimea of Nogales, Mexico, early last year.
Kelly has maintained his innocence throughout, rejecting a plea deal in January that would have lessened his charges to one count of negligent homicide.
His lawyer said Kelly shot into the air above the migrants, though prosecutors disagree with that notion, instead arguing he shot at the group of men.
Attorneys on both sides are disputing which evidence should be included in the trial.
Prosecutors secured an appeals court ruling in November that would allow them to call Kellys wife, Wanda, to the stand.
It is still uncertain whether text messages will be admitted as evidence.
The defense aims to introduce an expert witness to cast doubt on the investigation.
Kelly has been out on bond leading up to the trial, which again begins March 21 and is expected to last three weeks.