Hi Leon,
Actually, my links weren't even to say that alot of people DO get caught. They were just to point out the law. And I SO wish I had never used the 80/20 rule!!! It's a commonly used and accepted Six Sigma principle correctly known as the Pareto principle. But ANYWAY, I don't think I said anywhere that CBSA checks 80% of the people. Perhaps I didn't point out my use of the principle clearly enough. I was never trying to state as fact that CBSA checks out 80% of the people.
And you are absolutely right that there is no data on all the people that didn't get caught. And of course they don't all come here. Just like all the people that do get caught don't appeal the decision. Again, I thought it would be self evident that I was encompassing both arguements yet focusing on the other poster's only stated research methodology coming from this board. Once again, I guess I wasn't clear.
All I can say is that because of the type of work I do, I see a great number of people who do get caught. I also see a few who got away with it but then again, there will a greater number of the former in my office because of the nature of my work. Seeing what I see in real life, when I'm on this forum I feel obliged to be cautionary and advise people of potential consequences. And in my original response, you will note that I never said that the poster's father would not get into Canada unchecked. In fact, I told them what he should do if he did get in. But I happen to think his chance of getting checked or at least questioned is much greater than not. There we can agree to disagree. Maybe he'll get lucky and then good for him. But I still think he should know the risk he's taking. And like you, I will never advise someone on here to lie to CBSA or CIC.
All of this will be a moot point eventually once Canada implements wider issuance of biometric passports. There's also been greater chatter about passport exit controls but we will see about that.