It is best practice to keep all these items separate. ADA regulations do not make a distinction between current and former employees when confidential medical files are concerned. There is no specific law requiring I-9s be separate from personnel files but keeping them separate is a good defense against discrimination suits.
You should keep in mind that half of discrimination suits are filed by ex-employees. If you combine the files for ex-employees how can you prove they were ever kept separate?
Hope that helps you out. =)
A note about HR laws:
Laws concerning employee treatment, benefits, hiring and firingâ€¦etc are multi-level. What this means is that there are Federal laws, state laws and sometimes local regulations that have jurisdiction over an employee. The information presented here should not be considered legal advice. Ultimately, employers with serious legal questions should consult local attorneys with expertise in worker relations.
The questions and answers presented here are based on research and data from internet sources and should not be considered the final word.