Published: Jul 12, 2012 2:41 PM EDT

WEST PALM BEACH, Fla. (AP) - A Port St. Lucie teen accused of bludgeoning his parents with a hammer believes he has "such a strong defense" he'll reach a plea deal to avoid a life sentence.
    
But for now, 18-year-old Tyler Hadley has pleaded not guilty in the deaths last July of Blake and Mary-Jo Hadley. Police say Hadley threw a huge party at his parents' house after their deaths.
    
In jailhouse letters to friends and family, he expresses hope he can avoid a life prison sentence or be placed in a state hospital.
    
The teen repeatedly complains of depression in his letters, says he cries daily and prays for forgiveness.
    
The letters are part of a batch of documents made public by prosecutors.

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