Visit your local DMV office or access their website to obtain the necessary application for a medical exemption. Restricted Colors: California tint laws do not permit using red, amber or blue tint colors.Side windows must be colorless. Medical Exemptions: Some individuals may qualify for medical exemptions, allowing darker window tints. To legally tint windows, a car must display a sticker containing a certificate from the company that installed the tint or a manufacturer's name and address. You'll need a physician's note, a specific form, and a bit of patience to navigate the approval process with the DMV.