“To Peter Doig, this painting is kryptonite,” Chicago art dealer Peter Bartlow testified [...]

Expert witnesses took the stand on Thursday, as judge Gary Feinerman presided over a restless courtroom on the third day of the trial. The morning began with Tibor L. Nagy’s cross-examination of Bartlow, and focused on the techniques he used to authenticate the painting as Doig’s. “The Bartlow Method,” as Doig’s attorney sarcastically dubbed it, relied heavily on identifying small elements in the disputed painting that can be found in Doig’s verified work, such as the line of a skier’s right arm in a 1994 oil on canvas, Chopper, which Bartlow says is nearly identical to the ridge of a rock formation in the disputed painting.

The defense then called Richard Shiff, an art historian who calls himself “a connoisseur of [Doig’s] works.” He characterized Bartlow’s methods as “entirely unreliable,” adding: “If you go looking for coincidences, you’ll find them.” He also questioned Bartlow’s relationship with Fletcher, noting that the Chicago dealer stands to gain a 25 percent commission of the painting’s sale. “An authenticator should have no stake,” Shiff said.