As far as facts to back up Australian customs toughness, well for one their own records show that they screen every single piece of international mail to some degree. This is not true of the US for example, they only claim to screen 100% of high risk packages (whatever that means), not 100% of all international mail. Second of all we can see anecdotal evidence in that packages to Australia have been intercepted that do not seem like packages that would likely be intercepted if they were going to USA. Is the claim that Australian customs are extremely tough partially propagated by people who have heard it and started to repeat it, without having any information to back this up with? Certainly. Are Australian customs likely some of the toughest? I think that they quite likely are. I don't think that many western countries screen 100% of incoming international mail, and I doubt that Australia has the amount of incoming mail that the US does, although I am not sure on the exact statistics. Ability to get things by customs is obviously going to depend on a few things. We can probably assume that the skill of the agents of most developed nations customs are nearly equal, although this may even be a stretch as the skills of police in other areas varies significantly. We can probably assume that they have similar equipment as well, and that they are bound by similar privacy laws. What it comes down to then is the amount of money they spend on customs and the amount of incoming packages. I think Australia spends more on customs, per package, than most countries do, although again I am not certain of this. Really it is probably public record how much money is spent on customs and the number of incoming packages to a country. If we find that information I think we can have a more factually supported idea of which countries have the strictest customs.