FCRA stands for Fair Credit Reporting Act. Enacted in 1970, this federal legislation was initially designed to protect consumers who needed to correct inaccuracies on their credit reports. In the mid-90s, the scope expanded to include other types of consumer reports, such as background checks.
Your background checks MUST be FCRA compliant or else you'll run afoul of federal law, which can be equal parts problematic and costly (and this is especially true when it comes to the adverse action process). But here's the thing: you can't just worry about federal law. State and local jurisdictions also have legislation governing consumer reports, such as background checks. So whenever a background check is conducted, you need to consider compliance from three varying jurisdictional levels: federal, state, and local.