HALIFAX -- A navy intelligence officer rose before a judge in a Halifax court Wednesday to plead guilty to espionage and breach of trust, making him the first person in Canada to be convicted under the Security of Information Act.

Sub-Lt. Jeffrey Paul Delisle showed no emotion as he acknowledged to a provincial court judge that he understood the consequences of entering guilty pleas to three charges and was voluntarily giving up his right to a trial.

Defence lawyer Mike Taylor said his client decided about a week ago to end the matter that captivated the intelligence community and raised uneasy questions about the effect any leaked material might have had on Canada's relations with its closest allies.

"He's just wants to move forward, he wants to get it done, put it behind him, accept his responsibility and have the court deal with it," Taylor said outside court after the surprise guilty plea at the scheduled start of his preliminary hearing.

"This was simply a matter of deciding there's no good reason to simply put on a show for the public, to go through the motion when, in my estimation, the outcome was clear and Mr. Delisle was realistic about that."

Taylor said no deal was made with the Crown on possible sentences. The case returns to court Jan. 10 for a two-day sentencing hearing.

Delisle was charged with breach of trust and two charges of passing information to a foreign entity that could harm Canada's interests.

The 41-year-old was denied bail in March and has been in custody at the Central Nova Scotia Correctional Facility in Halifax since his arrest in January.

A broad publication ban was imposed on the hearing, limiting what can be revealed about the accusations against Delisle.

Federal prosecutor Lyne Decarie would not say what sentence she will seek. But she said one charge of breach of trust under the Criminal Code carries a maximum sentence of five years, while the other two charges under the security act carry life sentences.

Taylor said the Crown was asking for "significant numbers" in a federal institution, but not a life sentence.

The case against Delisle marked the first time someone had been charged under the act and his guilty plea is the first conviction under the federal law. The act was passed by the House of Commons after the terrorist attacks on the United States on Sept. 11, 2001.

Delisle wore a blue hooded sweatshirt, jeans and glasses during his brief appearance in court.

Delisle joined the navy as a reservist in 1996, became a member of the regular forces in 2001 and was promoted to an officer rank in 2008.

The officer worked at Trinity -- the name for the military all-source intelligence "fusion" centre on the East Coast -- which experts have said would provide tactical assessments primarily to Canadian warships and aircraft, both at home and overseas.

Defence Minister Peter MacKay insisted soon after the charges were laid that the breach did not damage Canada's relationship with its allies, saying "our allies have full confidence in Canada."