The 28-year-­old man accused of killing off­-duty Truro, N.S., police officer Catherine Campbell allegedly told police he punched and strangled her, according to documents obtained by CBC News that detail the investigation into her death.

Christopher Calvin Garnier is charged with second-degree murder and interfering with a dead body after Campbell's remains were found dumped near the Macdonald Bridge in Halifax last September.

The allegations are found in a sworn affidavit by RCMP Const. John Berger filed with the court to obtain a warrant for Garnier's DNA. The affidavit includes his summary of an alleged confession to RCMP Const. Joseph Allison made in the days after Campbell died. 

"He admitted to punching Ms. Campbell several times in the face and to strangling her with her hands," Berger swears in the documents. "He said he could hear her last gasp."

Berger was not present during the alleged confession.

Christopher Calvin Garnier

Christopher Calvin Garnier, 28, has a preliminary hearing scheduled for July. (Andrew Vaughan/The Canadian Press)

Campbell, 36, was first discovered missing after she failed to turn up to work in Truro on Sept. 14. Halifax police say they arrived at her apartment on Windmill Road in Dartmouth to find the TV on, her alarm clock ringing and two cats with empty food and water dishes, court documents say.

Police learned that Campbell left her apartment around 1 a.m. on Sept. 11 in a taxi to go to the Alehouse in downtown Halifax after a stressful week, documents say

She met Garnier at the bar where they kissed and talked, documents say. Police do not say if they found a prior connection between the two or if they believe they met for the first time at the bar. Garnier was there with a friend, who ended up in the drunk tank, the documents say.

Halifax Alehouse

Police allege in search warrant documents that Catherine Campbell and Christopher Garnier were seen leaving together from the Halifax Alehouse the night she died. (Dave Laughlin/CBC)

Video surveillance from the bar shows what police believe to be the pair leaving around 3:40 a.m. They arrived at Garnier's friend's house on McCully Street in Halifax around 3:45 a.m., the documents allege. 

About 45 minutes later, police say a man was caught on video surveillance rolling a green bin down Agricola Street and then North Street in his bare feet.
 
Police first interviewed Garnier on Sept. 15. During the interview, the police affidavit says he admitted to speaking with Campbell at the Alehouse, where he used to work, but denied going home with her. 

Agricola Street

Police allege in search warrant documents a man rolled a green bin down Agricola Street onto North Street the night Campbell died. (Dave Laughlin/CBC )

Campbell's body was found the next day over an embankment in a wooded area under the Macdonald Bridge near Valour Way, not far from North Street and Barrington Street. Her body was covered by an ottoman and the green bin was abandoned nearby, documents say.

On the morning Campbell's body was discovered, Garnier was seen driving toward the Macdonald Bridge, the documents allege. 

That afternoon, he was arrested near his home in Clayton Park and interrogated a second time.

"He admits that just prior to his arrest he was going to try and move her remains," a summary of the interrogation says

Police tape off area where Campbell's body found

In September, police taped off an area where Campbell's body was found near the Macdonald Bridge. (Craig Paisley/CBC)

The documents say he purchased a tarp, rope, bungee cords and a gas can, which police allege were found in his car with his passport and a receipt for Canadian Tire. Garnier told police he was planning to use the supplies to move Campbell's body, the documents allege.

The documents also allege Garnier said he considered fleeing, but did not want to leave his girlfriend. Documents say the couple "took a break" in their relationship, but got back together after the night Campbell died.

A medical examiner classified Campbell's death as a homicide and the most likely cause was strangulation. The warrant obtained by police was used to take a blood sample from Garnier to compare to male DNA found under Campbell's fingernails. 

According to the documents, police also searched the McCully Street home and found a T-shirt stained with Campbell's blood in a dumpster outside. Police also claim they seized Garnier's watch. Blood that matched Campbell's was found in the grooves of the watch face.

None of the allegations contained in the documents have been proven in court. Garnier is currently in custody and has a preliminary hearing scheduled for July. He has not yet entered a plea. 

Garnier's lawyer, Joel Pink, said in an email Thursday he was aware of the warrant for a blood test. 

"What counts is the evidence that is accepted by the trier of fact in open court," Pink said in the email. "The police are entitled to their views but the Crown and the defence are only interested in proven facts."

CBC News has posted the information to obtain a search warrant, which includes the police's version of events. The document has been redacted to protect the privacy of people interviewed by police. None of the allegations has been proven in court. 

CBC is not responsible for 3rd party content
With files from Blair Rhodes