(CN) - After his sleepwalking defense failed at trial, a man convicted of battering his girlfriend's son with a hammer won habeas relief from the Ninth Circuit.
The reversal published Friday says it was Yun Hseng Liao himself who called Los Angeles police after he picked up hammer from the floor and swung it three times at the head of his girlfriend's teenage son at about 4 a.m. on Aug. 2, 2002.
The boy pushed Liao to the ground and ran into his mother's room. Before going outside to meet paramedics, Liao told the mother he "had been dreaming someone was hitting him, and he had fought back," according to the ruling.
Worried he would go to jail, he told the boy to say he had fallen down the stairs.
The teen did not suffer any skull or brain damage, but he needed staples to close three cuts on his scalp, plus he suffered a concussion and broken bones in his hands.
Liao lived with his girlfriend and her family for four years prior to the attack, and he never hit the boy before.
The teen said Liao had hit his mother twice, though, and that the couple had been arguing the night before the hammer attack.
Before his trial, Liao's attorney hired Clete Kushida, a director of the Stanford University Center for Human Research and a board-certified physician at Stanford's Sleep Disorders Clinic.
Kushida recommended that Liao undergo a medical examination and a sleep study formally known as polysomnogram.
Though the Los Angeles Superior Court granted the sleep-study request, it never came to fruition because a court clerk erroneously told Liao's counsel that the motion had been denied. Liao's defense did not follow up on the false denial.
Without the medical results, Kushida testified that he could not diagnose Liao as a sleepwalker but did believe that Liao suffered from the condition.
A jury convicted Liao of assault and attempted premeditated murder for the attack on June 16, 2003.
Though sentenced to life in prison, Liao got out on parole in 2015 after serving 12 years.
Liao did not realize that he had been approved for the sleep study until his appeal. Though the state courts agreed that the performance of Liao's attorney at trial had been constitutionally defective, they said the failure had not been prejudicial.
A federal judge likewise denied Liao's habeas petition but the Ninth Circuit reversed Friday, saying the defective performance violated the Sixth Amendment.
"Liao was unmistakably prejudiced" by his trial's lack of a sleep study and the additional information Kushida sought, the 35-page opinion states.
Writing for a three-judge panel in Pasadena, Senior Judge Stephen Trott added that "the absence of a sleep study turned out to be the Achilles heel of Liao's defense."
"Counsel's error left Liao's defense weak and pregnable," Trott added. "It would not have been so with the evidence the jury did not hear because of counsel's mistake."
Though Liao is already out of prison, the District Court must takes measures on remand to grant him "a conditional writ of habeas corpus ordering Liao's release from all forms of custody unless the state of California elects within 90 days of the issuance of the mandate to retry him," the ruling states.
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