A free criminal background check can be obtained by contacting your State Department of Justice for criminal records or filling out a FBI Applicant Information Form. You can also use third-party services such as private investigators or online criminal record databases.
First, try contacting your local police department to find out if there are any records on file. Alternatively, some court records can be obtained through the National Center for State Courts. If you are unable to get records this way, try using the FBI archives, which requires you to submit an $18 for the application fee, a picture ID, and a set of recent fingerprint impressions before gaining access. This application can be located at FBI's website. If neither of these methods work, there are many third-party services to choose from.
Hiring a professional investigator can ensure a legitimate and complete background check, but such services can often be costly. There are also websites that have access to some criminal and legal records. Some of these websites include PeakYou, The Beat and national sex offender archives, which are widely available and frequently updated. Some third-party sites require users to pay a fee. Additionally, one can also try running a simple Google search to find information.