Most employers will now require that their potential employees pass a criminal background investigation before being extended an offer of employment with the company.  Conducting a criminal investigation prior to hiring a person reduces the risk of hiring a person that is unfit for the position or that may willfully harm the company through theft or fraud.

Most criminal background investigation reports will contain information from the public records found in every court system across the country.  Some high level positions may require a criminal investigation file from the Federal Bureau of Investigation, which has to be requested by the subject of the file and requires a fingerprint authorization from a police agency to verify the requester's identity.

In most cases, the cost of the criminal background investigation is paid by the company that is doing the hiring, as the cost of paying for multiple background checks could quickly drain the finances of a person searching for employment.  There are a few cases where the cost of the criminal investigation is the responsibility of the applicant, but this is generally not a barrier to employment because the level of detailed required in the background report means they can be obtained cheaply, or copied and used multiple times.