The lie detector operator Cartman Jasper is wearing glasses with no lenses in them. Update: When the camera is shooting from behind Cartman Jasper, the glasses do have lenses in them - the print on the chair that Nancy Gilman is sitting in is fuzzy and distorted. Update#2: It is extremely common in Hollywood for glasses not to have lenses in them when being filmed from the front. This is to prevent lights from reflecting off the lenses creating problems.