Closing arguments were made Wednesday in the murder trial of Mark Grant, who stands accused of killing Candace Derksen, 13.
The defence started its closing arguments Wednesday by saying the case against Grant is based on "bad science – bad science that ignored evidence. Science that is flawed, tainted."
Defence lawyer Saul Simmonds argued the DNA evidence in the case is unreliable and said the crime scene was not properly protected against contamination.
The Crown, meanwhile, argued previously that Grant's DNA was found on twine used to bind Derksen and said seven of Grant's hairs were found at the crime scene.
Derksen disappeared while walking home from school in November of 1984. Seven weeks later, her body was found bound and frozen in a shed.
In closing arguments Wednesday, Simmonds focused once more on DNA evidence.
"Those seven hairs...could have been Candace Derksen's," said Simmonds.
The defence suggested that the seven hairs were not tested against mitochondrial samples from Derksen.
"If you have a chain and there is one link missing, how strong is that chain?" Simmonds asked the jury.
In its closing arguments, which took more than an hour, the defence said the Crown's DNA experts were biased and ignored evidence that would exonerate Grant.
"You stand between the state and Mark Grant," Simmonds told the jury. "Your responsibility is to protect Mark Grant from a wrongful conviction."
In its own closing arguments, the Crown argued in support of the DNA evidence showing Grant was the killer.
"The probability, out of a randomly selected Caucasian population of anyone unrelated to Mark Grant, is one in fifty million," said the Crown.
The Crown needed about 20 minutes for its closing arguments.
The judge charged the jury with reaching a verdict Wednesday afternoon.
Court will resume once a verdict has be reached.
Derksen's parents were in court throughout the trial.
"There have been some excruciating moments. It felt like we were being skinned alive sometimes," said Wilma Derksen, Candace's mother.
CTV News asked her if she is hoping for a guilty verdict.
"Not necessarily. I'm hoping for the right decision - I trust the process to bring justice," said Wilma Derksen. "Yes, the verdict is important, but personally, we've experienced Candace. We've experienced her friends, and we've experienced healing."
