Chad Doerman, 33, was arrested after his sons were shot; authorities said a girl witnessed the incident, claiming her father was "killing everyone.
Judge Richard Ferenc stated that investigators failed to properly advise Doerman of his rights during interrogation, leading to the exclusion of statements.
Despite claims of upholding constitutional rights by the prosecution, the judge ruled in favor of barring statements obtained during the interrogation.
Doerman allegedly made statements during interrogation referencing biblical teachings, but the court deemed them inadmissible.
Authorities charged Doerman with aggravated murder for the deaths of his three sons, aged 3, 4, and 7, accusing him of planning and carrying out the killings.
The prosecution's case against Doerman is expected to proceed to trial in July.
The Clermont County Sheriff’s Office accused Doerman of lining up his children and fatally shooting them with a rifle, resulting in multiple charges, including aggravated murder.