Blood from a man accused of murdering a 15-year-old girl was found at her home, a jury in the High Court trial in Christchurch has been told.
The Crown says Dean Stuart Cameron, 39, a road worker, raped and murdered Marie Davis before dumping her body in the Waimakariri River in April last year.
Crown prosecutor Kathy Bell told the court Miss Davis was home alone on the night of 5 April listening to music on her computer. It is alleged the accused raped and murdered her some time after 3.30am on 6 April.
A car similar to Mr Cameron's was seen near the river that morning, the court was told.
The Crown says, although the cause of Miss Davis' death has not been ascertained, there are various mechanisms that could cause death without leaving a sign.
Ms Bell says Mr Cameron's blood was found at Miss Davis' home and semen detected from swabs taken from her body and DNA was consistent with being from the accused.
However, the defence on Monday questioned whether anyone killed the girl.
Lawyer Frank Hogan advanced several scenarios for the jury to consider, including whether Miss Davis went voluntarily to the river with someone else, whether she had a sexual encounter there and accidentally slipped into the river.
