So far in Torts, we have spent the bulk of our time learning about negligence. One key aspect of negligence law, as we are learning, is determining whether the defendant owed a duty of care to the plaintiff. In Canada, there is a test (known variously through time and space as the Anns, Anns/Kamloops, Kamloops, and Cooper tests - for reasons that I will not get into) for determining whether such a duty exists. It is a two-step procedure, the first step (essentially) being to assess if a duty exists, and the second being whether there are any policy reasons why this duty should be negated. One such reason is 'indeterminate liability' - basically, the court says "if we let you sue, even though the defendant owed you a duty, there is nothing stopping just about anybody from suing, so you can't do it."
The lesson for the Devil's Law Dictionary:
Indeterminate Liability (n) - If you are not going to fulfill a duty, make sure you owe it to as many people as possible.