Clayton Robert Weatherston was born on January 9, 1976, in Dunedin, New Zealand. 

On January 9, 2008, Clayton Robert Weatherston went to the home of Sophie Elliott in Dunedin, New Zealand. He arrived unannounced at around 12:30 PM. Sophie and her mother, Lesley, were packing for Sophie’s move to Wellington. Weatherston claimed he had a farewell present for Sophie. Shortly after he arrived, Lesley heard Sophie screaming.

A police officer, Constable John Cunningham, responded to a 111 call from Lesley. He found Weatherston locked inside Sophie's bedroom. When asked what he had done, Weatherston replied, "I killed her." He was immediately arrested.

The next day, forensic pathologist Martin Sage performed an autopsy on Sophie Elliott. He determined that she died from blood loss caused by multiple stab wounds. The autopsy revealed that there were 216 separate injuries, including wounds to her heart and lung, severe injuries to her neck and throat, and 7 blunt force injuries. Some of the injuries appeared to be defensive, indicating she had struggled during the attack.

In May 2008, the trial began after Weatherston was committed for trial by justices of the peace. He pleaded not guilty. The trial moved to the Christchurch High Court and was scheduled to start on June 22, 2009. Weatherston argued a defense of provocation and claimed self-defense.

The jury deliberated for five weeks before finding Weatherston guilty of murder on July 22, 2009. On September 15, Justice Judith Potter sentenced him to life in prison with a minimum non-parole period of 18 years. She stated that the killing was deliberate and controlled.

Weatherston's lawyers filed an appeal on October 13, 2009. They argued that he did not receive a fair trial due to heavy media coverage. On April 7, 2011, Weatherston's lawyer appealed the verdict on several grounds, including the influence of media commentary. However, on June 17, 2011, the Court of Appeal denied the appeal. The judges found that the original trial was fair. Weatherston later sought to appeal this decision, but the Supreme Court rejected his request on September 13, 2011.