Expert in sexual masochism testifies at Catherine Campbell murder trial

A psychiatrist who interviewed accused murderer Christopher Garnier sayshis description of being in a trance-like state following the death of off-duty officer Catherine Campbell is consistent with the symptoms of "acute stress disorder."

Dr. StephenHuckertestifiedWednesday for the defence in Garnier's second-degree murder trial in Nova Scotia Supreme Court in Halifax. Garnier, 30, is also accused of interfering with human remains. He has pleaded not guilty to both counts.

Huckerwas also asked to explain "erotic asphyxiation," saying it produces a sexual "high."Garniertestified this week that Campbell died after she asked to be choked and slapped at a Halifax apartment in the early hours of Sept. 11, 2015.

Garnierhas said there are many aspects of what happenedthat nighthe can't remember, including wheeling Campbell's body in a green compost bin and dumping hernear Halifax's Macdonald Bridge.

Hucker said Garnier's memory loss is a possible symptom of acute stress disorder. He also told defence lawyer Joel Pink that the loud noises Garnier reported hearing in his head, tunnel vision and a feeling of panic are also symptoms.

The psychiatrist testified he interviewed Garnier twice, but it was after the period in which he would have been showing symptoms. He has diagnosed Garnier with PTSD. Hucker also interviewed Garnier's girlfriend, Brittany Fraser, and his friend Mitch Devoe.

As for choking for sexual pleasure, Huckersaid people can fall unconscious very fast during erotic asphyxiation and give no warning signs before passing out, making it impossible to signal they're in trouble.

Hucker said people who regularly practise this kind of sexual activitytypically take safety precautions, including having a partner they can trust.

The psychiatrist's testimony was interruptedWednesday afternoon by an objection raised by the Crown after he answered a defence question about Garnier'smemory loss.

The jury was sent from the courtroom, and eventually instructed to go home for the night, as lawyers and the judge discussed the objection. Details of those discussions are currently banned from publication.

The CBC's Blair Rhodes livebloggedfrom court. Mobile users can readthe blog here.