They also say a police detective served as a "double agent" on the case, performing a lie detector test on Post for the defense team while working for the state to perform a similar test on an alleged conspirator in the motel shooting. The detective, "an agent of Post's defense team, violated a basic duty of loyalty and confidentiality to Post," the inmate's attorneys said.
"Lingering doubts exist about the degree of Ronald Post's legal and moral guilt," public defenders Joe Wilhelm and Rachel Troutman told the board in a written request for mercy.
"The death penalty should be reserved for cases where proof of guilt is reliable and the legal system produced a just result," they said. "Neither criteria is met in this case."
The Lorain County prosecutor argues that Post was the killer and as evidence points to Post's written no-contest plea in which he acknowledged responsibility for the crime.
That admission is "a compelling reason" why the board should reject clemency, Lorain County prosecutor Dennis Will said in a filing to the board before the hearing.
"Even though some of Post's personal admissions of criminal actions did not include an express and explicit personal admission that he was the shooter of Helen Vantz, all of Post's admissions amount to a confession by Post that he committed crimes at the Slumber Inn," Will wrote.
He also noted that Post signed a document prepared by the detective who conducted the lie detector test acknowledging he killed Vantz.
A federal judge plans a hearing later this month on Post's obesity claims.
Andrew Welsh-Huggins can be reached on Twitter at https://twitter.com/awhcolumbus.