Illinois forgery laws are broad and cover a lot of ground when it comes to altering, creating, or using fake documents or signatures to deceive. Common forms of forgery include altering checks, creating fake identification cards or licenses, or modifying legal contracts such as deeds and wills.Common example of forgery are presenting fake checks, fraudulent impersonation of another person or creating fake documents for property. Forgery is a type of fraud crime that often involves the creation of false documents or the alteration of otherwise legally valid documents. A person commits forgery when, with intent to defraud, he or she knowingly: (1) makes a false document or alters any document to make it false.