Originally published in The Times - November 23, 2017

Ely Sakhai, who ran a successful art forgery business in New York for 15 years, was caught only when Sotheby’s and Christie’s discovered in 2000 that they were both selling the same supposedly original work by Gauguin.

Now, thanks to computer technology, there might be an easier way to catch art forgers than waiting for them to make a mistake: researchers have found that the individual strokes in line drawings have specific characteristics that are impossible to replicate.