Like any survivors of an acrimonious divorce, they still bicker, fight over money and never quite let bygones be bygones. For the 26th anniversary of their separation, they will get a 4,000-page legal document chronicling just how dysfunctional their relationship once was.
The RCMP and CSIS, Canada's federal police force and its national spy agency, dread Thursday's release of the findings on the Air India tragedy. If past testimony is any indication, the agencies will be faulted for a bungled investigation, for contributing to a failed prosecution and for not converting spy "intelligence" to police "evidence."
After much delay, former Supreme Court justice John Major will finally revisit how Sikh extremists hatched a 1985 terrorist attack in Canada, killing 331 people by stashing suitcase bombs aboard passenger jets.
Mr. Major will be looking forward too, hoping to address ongoing problems. Many observers anticipate he will urge Ottawa to forge a better security union - possibly by addressing a vacuum at the centre. Insiders expect that a souped-up security czar in Ottawa could help the two agencies navigate the thorny intelligence-to-evidence quandaries that still beset them.
The Canadian Security Intelligence Service was carved out of the RCMP in 1984, a schism that created bad feelings and muddled missions even as robust teamwork was needed to tackle the nascent Air India mass-murder plot.
Ottawa had just created the closely monitored civilian spy service after a judicial inquiry found that the Mounties went overboard in clandestine campaigns against Quebec separatists.
CSIS was formed as a distant-early-warning system against espionage and terrorist threats. Agents would gather intelligence through surveillance. If threats elevated, the spies would tip the cops. The RCMP would gather "evidence," make arrests and push cases though court.
The system failed almost as soon as it was set up. CSIS destroyed surveillance tapes of its probe into Sikh extremists. The RCMP were unable to prove anyone guilty beyond a reasonable doubt - save for a lone terrorist convicted of a role in the bombing.
One former chief Mountie told Mr. Major that elements of an "almost unworkable" RCMP-CSIS relationship have persisted ever since. "If you see each other as competitors for those scarce resource dollars … then to enhance yourself you've got to put somebody down," former commissioner Giuliano Zaccardelli testified in 2007.
Sometimes his successors still hit the same note. "Has the focus on enhanced intelligence overshadowed the role of law enforcement?" RCMP Commissioner William Elliott said in a speech last fall. Complaining that CSIS had a greater share of counterterrorism riches, he said "we need greater capacity to put more terrorism cases before the courts."
At the same conference, CSIS director Richard Fadden said in his speech that court was the last place he wanted CSIS to be.
Yet Canadian judges place onerous obligations on police to disclose all potentially relevant documents to the accused. Police partnerships with spies pose huge problems, given the latter will scuttle court cases before risking exposing secrets.
There are successes. The "Toronto 18" terrorism case was launched in 2006 after CSIS handed over an investigation - and two human sources - to the RCMP. CSIS stayed in the shadows as courts convicted al-Qaeda-inspired youths.
The failures are less well known. A probe into an alleged Tamil Tiger front failed to yield significant charges, despite evidence of a money trail linking Sir Lankan terrorists to Canadian henchmen. Part of the reason, sources say, was that any RCMP prosecution risked exposing CSIS.
The Maher Arar affair and related cases were arguably intelligence-to-evidence failures, and judicial inquiries chronicled those missteps at length.
Now, it is Mr. Major who is set to advise CSIS and the RCMP on how to better team up to pursue terrorism cases - the third such report to be released in the past four years.