Bradley Rietze has received a life sentence with no chance of parole for 25 years for the murder of his stepdaughter Brittney McInnes.
Rietze stunned the judge and jury on Monday by dismissing his legal team and pleading guilty to first-degree murder.
For the first time details of the murder were read out in an agreed statement on Wednesday.
Court heard how Brittney was found by her aunt and sister hidden in the box spring mattress of her bed.
DNA from Rietze was found on the teen's body, under her nails and on the bathrobe belt that was used to strangle her.
Rietze admitted to sexually assaulting Brittney and then strangling her with the belt.
Brittney's family was in the courtroom and spoke about the impact of her death on their lives.
Her mother said that she can't stop the pain in her chest and told court her heart and family is broken.
A scholarship fund in Brittney's memory was established in November 2010.
For more information or to make a donation to the SuperBritt Scholarship Fund, click on the link.
