BATON ROUGE, La. -- Suspected serial killer Sean Vincent Gillis's attorney told a state appellate court his client's confession to West Baton Rouge Parish authorities was illegally obtained because investigators continued to question Gillis after he thrice told them he needed a lawyer.

WAFB-TV / File Photo

Sean Vincent Gillis.

But a prosecutor countered during a hearing at the 1st Circuit Court of Appeal that the interrogation of Gillis proceeded only because Gillis continued to provide information.

The 46-year-old Gillis pleaded guilty to second-degree murder in August 2007 in the Port Allen case and received a mandatory life prison term in the 1999 killing of 36-year-old Joyce Williams of Baton Rouge.

The 1st Circuit panel took the arguments under advisement.

Authorities say Gillis confessed to killing eight south Louisiana women between 1994 and 2004. He was booked in seven of those deaths. A probe into the eighth slaying is ongoing.

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Information from: The Advocate, http://www.2theadvocate.com

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