A friend I used to work for at a very small company reached out to me and asked if I would be willing to help them solve critical bugs and defects in an old application that they use and support. They have had a string of bad luck with prior contractors and he thought that since I have intimate knowledge of the quirks of this application that I would be the best person to most effeciently deal with them. I left the company several years ago as an employee on good terms.
He wants me to give him a quote to solve several bugs, which I agreed to. I told him what I would do is detail roughly what I suspect about the defect, offer a high level description of how I think it should be solved or investigated further, and then give him a rough estimate in hours to complete and deploy the defect resolution. In terms of a rate we agreed to work through that after we agree on the details of the quote. I mentioned to him that I have a day job and other responsibilities and that I cannot commit to any dates and that I will plan to work on this in any free time I happen to have. I planned on taking that restriction into account when discussing a fair rate.
The problem that I am struggling with is that my current employer requires all employees disclose any additional employment and that if we wish to take on additional employment then we must request approval from HR beforehand. I get that they dont want potential liability or conflicts of interest by working for a vendor or client of the company or even a direct competitor, but none of this happens to be applicable. My old company is very small, in a completely different industry, and while they had a brief vendor relationship with my current company at one point, that relationship ended several years ago.
Is this normal and legal in the US to require employees to disclose their other employment? Does this apply to self employment too where I am not an employee of another company but being contracted to perform some work? How can they even enforce such a policy? Just because I get a W2 from my current employer doesnt mean that they can necessarily see my other tax forms like 1099 other? How could they even find out if I decided not to tell them?