I can answer that. This is something that the Privacy Commissioner of Canada has also alluded to. There is no empirical evidence that no-fly lists advance aviation security at all. There is no evidence of that.
If you think about the logic of this, what you're suggesting is that some people are too dangerous to fly, but simply are not too dangerous to arrest, even on the grounds of conspiracy or anything else.
It's a deeply problematic notion, and there has been no evidence that it actually does what it says it does. We've raised this issue, and various other people have raised this issue, time and time again.
When you ask yourself what this kind of program is good for, it's good for surveillance and control of where people may go, but there is no evidence anywhere that we have been able to find or indeed that anyone who we've asked has been able to find--and that includes the Government of Canada relative to its own no-fly list--that this substantially increases aviation security.