I was reminded of that incident last August as I crossed into the US from the Mexican border town of Palomas. I was travelling with a photographer - a white Mexican with dual Spanish citizenship who, unlike me, did not have a visa to work as a journalist in the US. I thought there would be a problem. I didn't realise the problem would be me.
The border guard arranged for dogs to sniff my belongings and other guards to search my hire car, while she checked out my visa, asked me where I was born so many times I could barely remember, and made me explain every stamp in my passport. Meanwhile the visaless photographer had been waved through. Finally, when she had run out of fingers to fingerprint, she had to concede the possibility that I might actually be the foreign correspondent I claimed to be. Maybe she thought I should be taller.
The Home Office report, Exploring the Decision-Making of Immigration Officers, published last week, provides further evidence of what most non-white travellers have long known to be true. That the practice of profiling on the basis of race, ethnicity and religion persists at borders around the world. Compared to all the strip-searching, deportations and interrogations that go on, I have got off lightly. My granny was once questioned for more than three hours after arriving from Barbados. They wanted to know, among other things, whether she was coming to work. "Do you cut cane here too?" she asked.
These abuses are not systematic. According to the report, British immigration officers say they base their decisions on "instinct" or "intuition" about people who "look the part". On further inspection, these sixth senses turn out to be total nonsense - a grab-bag of "received wisdom" constructed from stereotypes that are anything but wise. "American ladies who've got loads of jewellery on ... their hair is perfect ... their makeup is perfect and their clothes are really nice," apparently get their approval. Young women in "white stilletos and short skirts", however, could be prostitutes.
But the abuses are systemic. For what looks like an individual's hunch is little more than the accumulated weight of assumption, presumption and prejudice, entrenched by global economics and sustained by local politics. Capital, we are told, must flow freely around the world to ensure international prosperity. The trouble is, this prosperity remains elusive to many in a world where about half the people live on less than $2 a day and the rules of international trade are weighted against the poor. Facing hunger and destitution, the poor move in search of work. But when they seek to gain access to the wealthiest countries - the very ones which created the rules that keep them poor - the doors are closed. Politicians desperate to galvanise popular support at home argue not for correcting the global inequalities in wealth but instead for stiffer immigration laws to keep the poor out. Since most, but by no means all, of these impoverished people are not white, racism almost inevitably informs and infects these immigration laws and the debate that surrounds them.
By the time it gets to the gatekeepers, the damage has largely been done. What immigration officers describe as instinct is, in truth, little more than playing the odds. "We're making decisions based on ... a balance of probability," said one immigration officer. In other words, they correctly intuit that there is a greater likelihood that non-white travellers will be poorer than white travellers and so stop them more often.
So non-white travellers fall foul not of the law of the land but the law of probabilities. The result is a vastly disproportionate number of black and Asian travellers who are stopped for questioning because on some level they "do not look the part". Non-white South Africans are 10 times more likely to be subjected to further questioning and non-white Canadians nine times more likely than their white countrymen.
The authors of the report insist that this has nothing to do with racism, insisting instead that socioeconomic factors play a key role. In other words, these people weren't more likely to be stopped because they were black but because they were poor and therefore more likely to be seeking work or drawing on public funds.
There are two main problems with this conclusion. First, it isn't true. Not only do the researchers provide no evidence for their conclusion. But the evidence they do provide suggests the contrary. When the figures were adjusted to take occupation into account, the discrepancy widened dramatically for all but the Americans. Non-white South Africans became 18 times more likely to be stopped and non-white Canadians 13.5 times. Moreover, when translated into sterling, the mean income of a black Canadian is almost double that of a white South African. Yet a black Canadian is four times more likely to be stopped than a white South African. Their efforts to understand race and class separately in this manner effectively lead to a complete misunderstanding of both.
Second, even if it were true, it is still wrong. For if the barriers to entry into the west are racist in practice, they are avowedly and unashamedly classist in intent. "For some immigration officers, credibility is essentially a matter of economics," states the report. In this particular respect, the officers are really just doing their job: actively excluding poor people who it seems no longer have the right to travel around the west with dignity and without suspicion.
The basic right to the freedom of movement was championed as one of the central criticisms of the eastern bloc. But as soon as the wall came down we built another huge one to replace it. True, in Europe we are gradually and grudgingly expanding its perimeters; but most of the world remains on the other side of it - and the wall is getting higher. Politics once kept people in; now economics keeps them out.
For the wealthy, however, it is a different matter. The report claimed that immigration officers have learned to "no longer ... ask a well-travelled American businessman how much money he has brought with him or for details of his bank balance". So the man most likely to steal your pension walks through without a word, while the one most likely to flip your burger or clean your house hugs the bottom of trains because legitimate means of entry are barred to them. So much for global citizenship.
So long as there are nation states there will be borders and immigration laws to regulate them. The least we can do is drop the pretence that these laws are fair. They are not designed to discriminate between people, but against them.