Removing Cox as conservator could improve the Powell family's standing in pursuit of $3.5 million in life insurance policies.
Terrica and Alina Powell's Utah attorney, Joshua Lee, told Dever the pair received notice that Cox became conservator after the fact, and Cox had no authority to change terms of the trust to remove his clients as trustees.
If the matter were a criminal trial, Lee argued, it would be akin to "saying you've been convicted of a crime and you can have a trial afterward."
Dever pressed attorneys on whether the law allowed Cox to exclude the Powells from participation in the trust.
"I'm not saying he can't act as conservator for her estate," Dever said. "The question is, can he modify the trust?"
The Coxes' Utah attorney, Donald Reay, said the trust's bylaws did not address what to do if Susan Powell went missing, but Utah law allowed him to become conservator.
Chuck Cox and his wife, Judy Cox, are from Puyallup, Wash., but were in the courtroom Wednesday. They have been represented by Seattle attorney Anne Bremner. Bremner told Dever the Powells challenged Chuck Cox's conservatorship in a proceeding in federal court in Washington and lost. Their challenge in Utah court, Bremner argued, amounted to venue shopping.
"Enough is enough. It's enough for this family," Bremner said as she raised her voice and pointed to Chuck and Judy Cox on the bench behind her.
The Powells "come here now because they haven't been winning in federal court in Tacoma," Bremner added. "And if they don't win here, they'll go back there. That's what the Powells do. They keep going and going."
The federal case in Washington is about whether Susan Powell's husband, Josh Powell, was within the law when he removed his wife as a beneficiary of life insurance policies after her disappearance and shortly before his death. Josh Powell killed himself and his two sons, 7-year-old Charlie and 5-year-old Braden, in a Feb. 5, 2012, fire at a rented home in Graham, Wash.
Josh Powell had been a person of interest in his wife's disappearance.
After the hearing, Chuck Cox said there have been no new leads on where his daughter might be. Earlier this year, he traveled Interstate 84 between Utah and Oregon distributing fliers asking the public for leads on where Josh Powell and his family might have taken Susan Powell. But Chuck Cox indicated he had no plans to resume.
"We're trying to deal with this mess," Chuck Cox said.