Customs officers miss the bleeding obvious

Last time I tried smuggling a deadly weapon across a national border, I slipped it inside a teddy bear and gave it to my sleeping child. It didn’t work: hard-faced customs officers disembowelled dear Edward and I spent ten malarial years in a Thai jail.

This is why we at TechEye were so very pleased to discover that a bunch of helpful eggheads at Duke University have been beavering away to make the smuggler’s life just a little less stressful.

What they’ve found is that if airport security employees have a long list of banned items – and let’s face it, there’s hardly anything you are allowed to take on board these days – they’re entirely likely to miss something lethal if they find a water bottle first.

Psychology and neuroscience professor Stephen Mitroff – who sounds like a wrong’un if ever I heard one – got interested in the topic in 2006, when the US Transportation Security Administration banned liquids and gels from all flights.

“The liquids rule has introduced a whole lot of easy-to-spot targets,” Mitroff said.

So he and his team asked college students to identify specific targets on a computer display which also contained roughly similar ‘distracters’. In some cases, the targets were easy to spot, and in others more difficult because they blended in with the background.

When there were the same numbers of each, subjects found box-cutters just as easy to spot as water bottles. But when the easy-to-spot item was two or three times more common, the subjects tended to miss the hard-to-spot targets.

When Mitroff’s group doubled the time allowed for each search, they saw that the students used barely a second of extra time but were way more accurate.

“It didn’t seem to do with time itself, but it seems to be the time pressure,” Mitroff said. “When you have the impending time pressure of going quickly, you are more likely to miss a second target.”

Professor Mitroff now feels he has exhausted the field of psychology. He plans shortly to shift his attention to pharmacology and explosives research.