By definition, it's a criminal offense wherein an individual, who is not the convict, interferes with the legal process by misleading the authorities by his words or actions. Simply put, any intentional interference with the due process of the law. However, to be held guilty, the person should be aware of the ongoing investigation. The principle statutes of crime related to obstruction of justice have been enlisted in Chapter 73 of United States Code, Title 18, Section 1501 to 1518.