An autopsy performed on 34-year-old Kristy Huddleston showed she died from a gunshot wound to the head.
Jackson County medical examiner Dr. James Olson ruled Huddleston's death a homicide in his report, according to the Jackson County Sheriff's Department.
In addition, the Oregon State Crime Lab is examining ballistics and other evidence collected from Huddleston's home on Pioneer Road near Medford.
Police responded to the home March 23 and found the bleeding Huddleston inside.
Deputies then tracked her husband, Bourne Huddleston, 43, to a home in Eagle Point and arrested him on a murder charge.
Police said the couple's 10-year-old son was inside the home when the shooting occurred.
Jackson County sheriff's spokeswoman Andrea Carlson said the investigation is continuing.
"We are still looking into it," she said. "There are some things we will need to finish up."
The Jackson County District Attorney's Office will present the case before a grand jury on Thursday, Carlson said.
The grand jury will decide whether Huddleston will be indicted on charges of murder, attempted aggravated murder and attempted murder, soliciting aggravated murder, soliciting murder and possession of a silencer.
"Even though we are not finished with our investigation, the case can still be presented before the grand jury," Carlson said.
The district attorney's office believes Huddleston tried to hire someone to kill his wife prior to the shooting.
Kristy Huddleston worked as a nurse case manager at the U.S. Department of Veterans Affairs. She aided returning military veterans in reintegrating into the community following their service.
Murder carries a mandatory minimum sentence of 25 years, attempted aggravated murder carries a 10-year sentence and attempted murder carries a mandatory sentence of 71/2 years.
— Chris Conrad