The Illinois Petition for Certificate of Innocence is a legal document filed by a person who has been convicted of a crime in the state of Illinois and believes they are innocent. The petition requests the court to vacate the original conviction and issue a Certificate of Innocence to the petitioner. This Certificate, if granted, is a formal declaration that the petitioner is innocent of the crime for which they were convicted. There are two types of Illinois Petition for Certificate of Innocence: post-conviction and pre-trial. The post-conviction petition is a claim that the petitioner is innocent of the crime for which they were convicted; whereas the pre-trial petition is a request to vacate the criminal charge and issue the Certificate of Innocence before the trial process begins. In either case, the petitioner must prove their innocence by a preponderance of the evidence.