The murder trial in the death of Candace Derksen continued Friday with court hearing from a doctor who pronounced the 13-year-old girl dead after she was found bound and left in a shed in November 1984.

Dr. Peter Markesteyn, a former chief medical examiner, testified Friday that hypothermia was the cause of death.

"She lost consciousness pretty fast, but it may have been hours before her death," testified Markesteyn.

He told court it was likely Derksen died within 24 hours of ending up in the shed in Elmwood, less than 1 km from her home.

A medical examination indicated Derksen was alive when she was bound, he said.

Dr. Markesteyn testified about the condition of Derken's body and clothes. He said he found no semen on her body.

The only sign of injury to her body was on her knees, believed to be from kneeling on the shed floor, said Dr. Markesteyn.

In cross examination, Dr. Markesteyn said he could not say exactly when Derksen died.

He said that during Derksen's autopsy, the medical examiners and police officers present did not wear hair nets or face masks and their faces came within close proximity to Derksen's body during the examination.

Mark Edward Grant faces a charge for first-degree murder in the case.

Derksen disappeared while walking home from school in November of 1984. She was found dead seven weeks later.

In 2007, Grant was charged with first-degree murder after a cold-case unit began investigating the case.

Grant has pleaded not guilty in the case.

A friend of Derksen's who saw her earlier in the day before she disappeared in November 1984 is taking the stand Friday afternoon to offer testimony.