Canada has a national police force and a mostly domestic intelligence service, the Canadian Security Intelligence Service (C.S.I.S.). These organizations haven’t always worked well together. Spies and police have been known to unproductively chase the same targets. And spying has complicated police efforts to bring charges in open court: The C.S.I.S. often tries to protect its sources and methods in criminal proceedings that demand full disclosure.

The investigation into the 1985 Air India attack, when a bomb exploded on a plane en route from Toronto to New Delhi, killing 329 people, is a prime example of this disorganization. In 2010, a judicial commission of inquiry found that efforts to detect and prevent this attack had been undermined by a fundamental lack of cooperation between Canada’s spies and police, and urged reform. Bill C-51 rejects these calls, giving primacy to the C.S.I.S. and empowering it to carry out investigations without police assistance.

Bill C-51 would authorize the C.S.I.S. to “take measures, within or outside Canada, to reduce” national security threats. The government argues that this would enable a range of valuable actions, like allowing C.S.I.S. agents to speak with parents of potential terrorists. But the real endgame could be much more concerning. If the bill is passed, the C.S.I.S. could have the capacity to do things like block the return of Canadians fighting abroad; remove Web postings it found threatening; drain bank accounts; engage in disinformation campaigns; or bypass traditional police channels in order to detain suspects. The only limits explicitly spelled out in Bill C-51 are acts that would cause “death or bodily harm,” willfully obstruct justice or violate sexual integrity.

The bill’s main safeguard would be judicial warrants, required when potential agency actions would contradict Canadian law or contravene rights enshrined in the country’s Charter of Rights and Freedoms. But this safeguard is imperfect. C.S.I.S. warrant proceedings are secret and one-way: The target of the requested warrant is not represented. Such proceedings always run the serious risk of wrongly penalizing an innocent person. This trade-off may have been (barely) acceptable when requests were limited to surveillance. But Bill C-51 could see Canadian Federal Court judges asked to authorize lawbreaking or unconstitutional behavior by a covert agency whose mandate would extend beyond spying.

If foreign governments have thus far eschewed commenting publicly on the proposed legislation, two features should stand out for the international community. Bill C-51 would permit C.S.I.S. interventions beyond Canada’s borders. And it would even empower Canadian courts to authorize C.S.I.S. conduct that violates “any other law, including that of any foreign state.”