UK Borders Bill
1:30 pm
Professor Ross Anderson: You can of course tweak a system so that you can adjust the number of false positives versus false negatives. That opens the question of who will do the tweaking and what the institutional incentives will be. Another raft of issues comes along when you start thinking about using a national identity document in financial transactions. Banks tend to have a very different idea of what the trade-off between false positives and false negatives should be.
One reason why the banks have not introduced biometrics for, let us say, card payments is that they are very reluctant to insult their customers. They reckon that a fraud rate of 1 in 100 is acceptable provided that the insult rate is no more than 1 in 100,000. I rather think that police, immigration, the Home Office and so on might take a completely different view of false negatives and false positives. I do not see any evidence that such issues are being thought about.