Sen. Pam Roach, R-Auburn, filed the bill in Washington's legislature. The bill's summary says it would be "prohibiting a child custody award to a suspect in an active murder investigation."
"If someone is charged with murder or manslaughter, had children and wanted custody or visitation, they would have to agree to allowing some of the information to the appropriate authorities," Roach said in an interview with FOX 13 on Wednesday.
Josh Powell was never declared a suspect in his wife's 2009 disappearance. Roach said court documents filed in the child custody case involving Charlie and Braden indicated otherwise.
"We knew that Josh Powell was under a murder investigation," she said. "You called it 'missing persons.' "
Powell killed himself and his children in an explosion and fire at their Graham, Wash., home on Feb. 5. West Valley City police have referred to him as a "person of interest" in the disappearance of Susan Cox Powell.
Meanwhile, questions have been raised about any involvement by other members of Josh Powell's family in Susan's disappearance. Washington state authorities confirmed that Josh Powell's father, Steven Powell, took sick days immediately after she vanished. It coincides with an 800 mile trip police allege Josh Powell took in a rental car.
"They specifically list in there, cell phone conversations with Josh and his dad the day that Susan went missing," Susan's father, Chuck Cox told the FOX News Channel on Tuesday. "I'm convinced that his dad knew everything that was going on, if not helping it."
Steven Powell is jailed, facing trial for voyeurism and child pornography. He has refused to cooperate with law enforcement.
West Valley City police declined to comment on the case on Wednesday, saying the investigation is "ongoing."