With facial recognition, for example, a person whose details are already held on file can establish who they are by showing their face to a particular camera. Fingerprints and irises offer other forms of biometric recognition, and technology to analyse gait and handwriting is also being developed.In the United States several categories of passengers, including citizens and many visitors, can use machines to verify their identities, followed by a brief chat with an officer, which has sped up the process of entering the country.
The technology is growing in popularity for precisely this reason: it offers a way to process passengers through airports faster and more cheaply. The airline says that by using biometric boarding gates in Los Angeles it can get 400 passengers onto a plane in 22 minuteshalf the usual time.
Americas Department of Homeland Security, for example, says it will keep the scans of its citizens for 14 days, though there are doubts about whether it should be doing this without congressional approval. Facial-recognition systems still have sizeable error rates, and certain systems perform worse with black people and women, according to a report published last year by Georgetown Universitys law school.