Aug 16 (Reuters) - Homicide detectives should have stopped questioning a criminal suspect who said that his father had advised him to ask for a lawyer, a federal appeals court ruled on Thursday.

A divided 11-judge panel of the 9th U.S. Circuit Court of Appeals in San Francisco found that Tio Dinero Sessoms had asserted his right to an attorney when he relayed his father's advice to the officers. The ruling requires police honor even ambiguous requests for counsel that a suspect makes before being informed of the right to an attorney, known as Miranda rights.

The case dates back to a 1999 home burglary in Sacramento, California, in which one of Sessoms' accomplices committed a murder. Sessoms fled from California to Oklahoma where, at the urging of his father, he surrendered to police.

During his interrogation, Sessoms was recorded on video saying "There wouldn't be any possible way that I could have a...a lawyer present while we do this?" He continued with, "My dad asked me to ask you guys...uh, give me a lawyer."

The detectives told Sessoms that having a lawyer would only hurt him and would also be futile because his accomplices had divulged everything. The officers then read Sessoms his Miranda rights, which he waived, proceeding to implicate himself in the crime. He was ultimately convicted and sentenced to life in prison without the possibility of parole.

On appeal, both a California state appeals court and a three-judge panel of the 9th Circuit found that the state had not violated Sessoms' right to a lawyer because his requests were too ambiguous. But a larger panel of the 9th Circuit disagreed.

"Although it was couched in a polite and diffident manner, the meaning of Sessoms's request was clear: he wanted a lawyer then and there," Judge Betty Fletcher wrote for a six-judge majority. Even if the request had been ambiguous, suspects are held to a lower standard of clarity before they waive their Miranda rights, the majority concluded.

Five judges on the panel dissented, saying requests for an attorney must be clear both before and after the Miranda warning is given, and Sessoms failed to meet that burden.

"A reasonable jurist could conclude that telling a detective 'My dad told me to ask for a lawyer' is different than saying 'I want an attorney,'" Judge Mary Murguia wrote for the dissenters.

The 9th Circuit sent the case back to the lower court for Sessoms to be retried or released.

A spokeswoman for the California Attorney General's Office said prosecutors were reviewing the decision and declined further comment.

"If we had lost, it would have been a substantial erosion of the Miranda rights," said Eric Weaver, a lawyer for Sessoms. He said the decision prevents police from using an ambiguous request as an opportunity to engage in further questioning and talk defendants out of exercising their right to a lawyer.

The National Association of Criminal Defense Lawyers had supported Sessoms in the case, arguing that no "magic words" are required to assert the right to counsel.

The case is Sessoms v. Runnels, 9th U.S. Circuit Court of Appeals, No. 08-17790.

For Sessoms: Eric Weaver of the Law Offices of Eric Weaver.

For Runnels: Jeffrey Firestone of the California Attorney General's Office.

For the National Association of Criminal Defense Lawyers: Peter Pfaffenroth of Sidley Austin.

(Reporting by Terry Baynes)

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