The party's critics for public safety, defence and foreign affairs joined Sen. Romeo Dallaire to call for greater parliamentary scrutiny of national security matters.
The Canadian Press reported this week that the Canadian Security Intelligence Service monitored Delisle for months but ultimately left it to the U.S. FBI to brief the RCMP on the case because of fears about intelligence secrets being disclosed in criminal court.
Delisle was sentenced this year to 20 years in prison after pleading guilty to passing classified western intelligence to Russia in exchange for cash on a regular basis for more than four years.
At one point the Americans, worried about the continuing breach of top-secret allied information, floated a plan to lure Delisle to the U.S. and arrest him themselves.
Liberal public safety critic Francis Scarpaleggia says Canadians are justifiably concerned about the apparent mishandling of the file.
John McKay, the party's defence critic, said Thursday that Delisle should not have been allowed to continue divulging important information.
Dallaire has proposed a motion to have a special panel of senators examine and report on creation of a national security committee of parliamentarians that would have access to classified information.
"In the end, Canada is lagging behind the rest of the world when it comes to oversight for our intelligence, public security, and anti-terrorism activities," Dallaire said.
"Parliamentarians lack the tools and the venue they need to do our jobs properly, and to hold these institutions to account on behalf of all Canadians."
Liberal foreign affairs critic Bob Rae reiterated his call for a judicial review of the Delisle case.
"Every other major breach of security in Canadian history has been followed by a judicial inquiry. This should be no different," he said.
Rae once led a review of the 1985 Air India bombing that documented problems between the RCMP and CSIS.
"If this is still the case, we should know about it, and the Harper government should fix it," he said.
The NDP has also been pressing the Conservative government for answers on the Delisle affair.
Public Safety Minister Vic Toews has said little about the latest revelations.
On Wednesday, Toews advised NDP public safety critic Randall Garrison that if he had any information about security forces behaving contrary to Canada's interests, to immediately refer it to the Security Intelligence Review Committee, the watchdog over CSIS.Suggest a correction