Juvenile killer Tyler Hadley returns to court Monday before St. Lucie County Judge Gary Sweet for day six of his resentencing hearing.

Hadley, 24, was convicted four years ago in the July 16, 2011, beating deaths of his parents, mother Mary Jo, 47, and father Blake Hadley, 54.

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He was 17 when he used a claw hammer to bludgeon the couple to death.

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In 2014, Hadley pleaded no contest to two counts of first-degree murder with a weapon and was sentenced to two life prison terms. An appeal he won threw out his life terms and sent the case back for a new sentencing hearing.

Hadley still faces a punishment of life in prison, but he could get as little as 40-years. It could be weeks or months after the hearing for Sweet to impose a new sentence.