The question is – there is negative information in your personnel file at your job, and your employer won’t let you review it, see it, add to it, change it – is that legal?
And the answer, unfortunately, is, yes. It’s perfectly legal because the employee personnel file at your workplace is your employer’s proprietary information. You, as the employee, don’t have any right to put anything into it, to take anything out of it, even to review it. It’s not your file, it’s their file – even though that seems kind of counterintuitive.
What you can ensure that they don’t do is to reveal the contents of that file to others, to prospective employers, or really to anyone outside of the workplace because once you are no longer working for the company and you apply for other jobs, that company is not in a position to tell other employers how they feel about you. As a general rule, employers only reveal the dates of your employment, the title of the last position that you held, salary information only if you authorize that in writing, and nothing more. So while your employer can jot down whatever it wants to put in your file, you’re not entitled to it and no else is going to see it, so it won’t harm you later on down the road.