Where an expert testifies in court, the opposing counsel must be permitted to cross-examine him or her about the sources of evidence which form the basis of the opinion.The 1st District Appellate Court reversed and remanded a decision from Cook County Circuit Judge Thomas J. Lipscomb.On Oct. 10, 2013, Scott Gilman ran over the left foot of Sweta Karn while making a left turn at an intersection. Karn suffered severe and permanent injury to the foot and filed suit against Gilman and his employer, Aspen Commercial Painting …