Prosecutors had requested Grant Ruffin Haze, and his wife, Amanda Perry Haze, be tried together. The pair are charged with murder in connection with Laura Ackerson's death.
Ackerson's remains were found in Oyster Creek near Skinner Lane in Richmond, Texas July 2011. Identification was made through dental records days later. The 27-year-old was reported missing on July 18.
Texas deputies said they believed Ackerson was killed in North Carolina, and then dismembered, before her body was taken to Texas in coolers. The creek where the remains were found is near Amanda Haze's sister's home.
When neither of the Haze's attorneys objected to a joint trial Friday, the judge ruled their trial would start May 20.
However, the judge said the arraignment could change during the trial if one of the defendants should offer evidence the other feels is damaging to their case.
"The fact that either and both consent today, or do not object today, does not preclude either defendant from raising the issue of whether or not something has happened during the trial that has changed the posture of a joint trial that would therefore preclude the state from proceeding against both in the presence of a jury and move to sever one," Wake Superior Court Judge Donald Stephens said.
If that were to happen, the judge would have to decide which defendant would continue to be tried and which would be tried later.
During a 2011 court hearing, an assistant district attorney told a judge that Haze wanted Ackerson out of his life.
Ackerson and Haze had been involved in a custody battle over their children for more than a year. Haze was later granted primary custody in 2010.
Estranged family members of Ackerson have said they wished they had stepped in sooner.
"Very controlling and very manipulative," Ackerson's brother Jason Ackerson told ABC11 in a previous interview. "It was hard to contact her without her getting in fear of her life from her ex-boyfriend. And we should have taken the threats more seriously."
Grant Haze was a local musician in Raleigh.
Prosecutors said he legally changed the spelling of his last name from Hayes to Haze, so they now refer to him as "Grant Haze, a.k.a. Grant Hayes."