Canadian naval intelligence officer Sub-Lt. Jeffrey Delisle is at the centre of what's being called Canada's biggest spy scandal in more than half a century.

Delisle was posted to the security unit HMCS Trinity, an intelligence facility at the naval dockyard in Halifax. It tracks vessels entering and exiting Canadian waters via satellites, drones and underwater devices. The centre is a multinational base with access to secret data from NATO countries.

The RCMP arrested Delisle on the weekend of Jan. 14, 2012, and charged him with violating the Security of Information Act. The charges against him included breach of trust and two counts of communicating information to a foreign entity without lawful authority that the government of Canada or a province has taken measures to safeguard.

On Feb. 8, 2013, a Nova Scotia judge sentenced him to 20 years in prison.

Details about his life are sketchy, but he is known to be divorced and has custody of three of his four children. One source is an old MySpace page that Delisle seemed to have neglected for a few years. He listed his interests as computers, reading, firearms, gardening, Monday Night Football, fishing, camping and canoeing.

Here are the known events in Delisle's life, and the espionage case.

June 1990

Jeffrey Paul Delisle (born in 1971) graduates from Sackville High School in Lower Sackville, N.S. "Jeff was a sort of person who just blended into the background," high school chum Greg Auton told The Globe and Mail.

January 1996

Delisle joins the reserves as an intelligence operator, serving with 3 Intelligence Company in Halifax. The group conducts intelligence gathering operations.

May 3, 1997

Delisle marries Jennifer Lee Janes in Lower Sackville, N.S.

Feb. 17, 1998

Delisle files for bankruptcy. Records show he declared liabilities of $18,587 and assets of $1,000. His listed address was on Beaver Bank Road, near his old high school.

March 2001

Delisle leaves the reserves and enrols as a regular member of the Canadian Forces. According to former neighbours, around this time, the Delisles move into a co-op in Lower Sackville for low-to-moderate-income households.

October 2001

Delisle completes a junior leadership course, obtains the rank of corporal.

2004

At some point in this year, the Delisles' two young daughters are hit by a vehicle a block away from their home. One of them ends up in hospital, and for years, Delisle would pursue the offending driver for money.

November 2006

Delisle is promoted to sergeant.

2006

Delisle begins working at the chief of defence intelligence office in Ottawa.

The family takes up residence near the suburb of Orleans, Ont. A former neighbour of the Delisles later recalls a day in 2007 when she saw Delisle hiding behind a hedge to see what his wife was doing at the home of another man in the neighbourhood.

2007

Delisle starts a stint at the strategic joint staff division in Ottawa.

According to material from a bail hearing, Delisle walked into the Russian embassy in Ottawa one day wearing a red ball cap and civilian clothes. He flashed his Canadian military identification and asked to meet with someone from GRU, the Russian military intelligence organization. The documents say Delisle offered to sell secrets to that country's military intelligence agency.

July 6, 2007

According to the RCMP, Delisle first breaches a trust or communicates safeguarded information. The Mounties have yet to elaborate on the details of this breach.

In Halifax, Delisle was working on a system called the Stone Ghost, said CBC reporter Rob Gordon, who reviewed court documents related to the case. "It's a computer system that links the five eyes. The five eyes are the United States, Britain, Australia, New Zealand and Canada. All their information is shared on the Stone Ghost computer.

"He would go to work every time with a thumb drive and download reams of information, which he would then send to the Russians on a monthly basis. And this went on for years and years and years."

Delisle was paid $3,000 a month for the information.

2008

Delisle enrols in the faculty of arts at Royal Military College in Kingston, majoring in politics. This is part of a university training plan for non-commissioned members of the Canadian Forces.

June 2008

Delisle and his wife sign a separation agreement, which stipulates that Delisle assumes the couple’s debts on three credit cards and a consolidated loan. The Delisles' eldest daughter, Angelica, stays in Gloucester, Ont. with her mother, while Delisle takes custody of the remaining children – daughter Victoria and sons Noah and Jonah – and moves with them to Kingston, Ont.

July 2008

Delisle receives a commission, becomes a naval officer.

2009

Delisle tells the Russians he wants to stop dealing with them. In response, they send him a photo of his daughter walking to school in Halifax.

According to court documents, Delisle is instructed to meet his GRU handler in Brazil, where he is asked to become a Canadian pigeon, an espionage term for a person who deals with all the secret operatives in an area. Delisle agrees and is handed $50,000. When he lands at the Halifax airport, customs agents want to know why he only spent a few days in Brazil and why he had thousands of dollars in cash. They notify the military, which begins an investigation with the RCMP.

May 3, 2010

The Delisles file for divorce. According to the National Post, a number of residents in the Delisles' condo complex said it was an affair that brought their marriage to an end.

September 2010

After graduating with a BA from RMC, Delisle joins the Land Forces Atlantic Area Headquarters in Halifax. Delisle's youngest daughter and two sons accompany him to Nova Scotia.

August 2011

Delisle joins HMCS Trinity, an intelligence facility at the naval dockyard in Halifax that tracks vessels entering and exiting Canadian waters via satellites, drones and underwater devices. The centre is a multinational base with access to secret data from NATO countries.

December 2011

Delisle's house is raided as part of the investigation by the military and the RCMP.

Jan. 13, 2012

According to the RCMP, this is the date that Delisle last breached a trust or communicated safeguarded information.

Jan. 14-15, 2012

Delisle is arrested by the RCMP. He is charged with breach of trust and communicating safeguarded information to a foreign entity without lawful authority. Delisle is the first person charged under Section 16(1) of the Security of Information Act.

Delisle is led out of a Halifax court on Jan. 16. (Andrew Vaughan/Canadian Press)

Delisle's neighbours in the Halifax suburb of Bedford told the Halifax Chronicle Herald that after his arrest, the woman and three children he was living with moved out of the family home.

"On Wednesday [Jan. 18], no cars were in the driveway, and blinds covered the windows," reported the Herald's Selena Ross. "Three bed frames and mattresses, including two single-sized children's beds, leaned against the side of the house."

Jan. 17, 2012

Delisle's lawyer, Cameron Keen, attends Delisle's bail hearing in Halifax and requests a delay in order to have more time to prepare, but Delisle does not appear. A hearing is set for Jan. 25. He is being held at the Central Nova Scotia Correctional Facility in Dartmouth, N.S.

At an Ottawa news conference, Defence Minister Peter MacKay says the case is a matter of national security because of the charges involved.

Jan. 23, 2012

The military evacuates HMCS Trinity in order to search the naval communications and surveillance centre for evidence of espionage or devices meant to leak information to the outside.

In a separate development, Delisle’s lawyer, Cameron MacKeen, quits the case. He does not explain why, or whether his ties to the Conservative Party and Peter MacKay influenced his decision. Delisle retains his new lawyer, Mike Taylor, on Feb. 27.

March 30, 2012

Judge Barbara Beach denies Delisle bail after hearing evidence from three defence witnesses and one witness for the Crown two days earlier. A publication ban on evidence is in effect.

May 8, 2012

Delisle's case is put over until June 13 and then put over again to July 4. Delisle's lawyer said he did not have full disclosure from the Crown.

July 4, 2012

Delisle's lawyer, Mike Taylor, requests more time to review documents, of which he said there are thousands. He is granted two more weeks.

July 17, 2012

Delisle elects to have his case heard in front of a judge and jury in Nova Scotia Supreme Court.

July 18, 2012

The court sets Oct. 10 as Delisle's preliminary hearing date.

Oct. 10, 2012

In a surprise move, the intelligence officer pleads guilty in a Halifax court to breach of trust and two counts of passing information to a foreign entity between July 2007 and Jan. 13, 2011, in Ottawa and Kingston, Ont., and Halifax and Bedford, N.S., where he lived.

Jan. 31, 2013

Deslisle's sentencing hearing begins in a Nova Scotia provincial court. The Security of Information Act lays out an array of breaches, ranging from threatening the safety of the Forces to selling software and the technical details of operations. The Criminal Code charge can net a five-year prison sentence, and convictions under the Security of Information Act can lead to life in prison.

Feb. 8, 2013

Nova Scotia court Judge Patrick Curran sentences Delisle to 20 years in prison for "coldly and rationally" selling secrets to Russia. Delisle will spend 18 years and five months in jail, because of time he has already served. The defence had asked for a nine to 10-year sentence, while the Crown had a sought a 20-year sentence.