Proof of employment eligibility can include several pieces of documentation. All job offers are then contingent upon the applicant passing the drug test. There will be a place on the application for you to sign agreeing to this procedure. Casinos that have this policy in place notify applicants that they will be tested if offered a job and request their consent in writing. Most major casinos now screen all new hires for drug use. Chances are you will also be asked to consent to a drug test and, as with most jobs, to provide evidence that you have the legal right to work in the United States.