Dear Pants on Fire,
Not knowing your definition of “very bad” it’s hard to offer specific advice. However, let’s look at a couple of scenarios.
If it is a crime separate from work do not cover it up. You don’t need to stress out and worry about being discovered at any moment. You will suffer the consequences, so report it to the authorities. Get legal advice if needed. No job is worth it.
If it is a work violation (falsifying records, taking kickbacks, selling inferior products, harassment or assault at work…the list goes on), then report it to the appropriate internal team. There is likely a hotline to report company violations. Review the employee policy manual to find out what to do. Otherwise, contact HR for guidance. Don’t be afraid of losing your job. Most companies have a policy about retaliation, so you are likely protected there. If not, you can get an attorney and file a lawsuit. But, most policy manuals are crystal clear on this and it’s even covered in compliance training.
Good luck. I hope this helps!
Originally published on Quora