Clarification on Legal Implications of Excess Payment
The points you have raised are important but were not the focus of the original post. The original query did not seek advice on actions against the person who made the mistake. I assume either that has been dealt with, or that the person who made the mistake is the one posting :) This being an HR forum, I focused on that part.
Let me clarify, I have not checked back on the exact wording of the Payment of Wages Act (I was not in the office and didn't have the time to search online). Instead, I referred to a doctrine in law called the doctrine of equity. Applied to labor law, the courts in India have been taking a very liberal view of it. Basically, they are saying that the courts will support the labor in any case that puts them at a disadvantage or in any attempt to deprive them of their rights.
Here we are talking about a case where a company has made a wrong payment. Yes, if you pay someone wrongly, you can, in the next month, deduct that money from their salary. Perhaps if it happened for 2 months at a stretch, again, you can recover it. There is even a clause in the Payment of Wages Act that can be stretched to allow it (repayment of advances).
However, if you have been paying a higher amount consistently for 3 years, the courts will definitely take a stand that it is deemed to be the correct amount. The workers are getting it. Everyone (or a specified portion) of the workforce is getting it. You cannot suddenly say it was a mistake and want it back. The court will not allow it. There is also something called the doctrine of promissory estoppel, which says when you have acted in a manner that induces people to believe in a certain fact (in this case, that their salary is indeed higher), and that they have acted on that in good faith (here, it is that they have spent it), then you can't say afterward that it is not a fact (I gave a simplified version. This was a whole chapter in my law book).
Further, what I was saying is that the unions will not allow it. No union worth their salt will allow or agree where it has been paid for 3 years. It will be an industrial dispute and definitely a ground for a strike. And yes, the conciliation officer, labor officer, factory inspector, authority under the Payment of Wages Act, everyone is going to rule against you on the merit that you have paid it for 3 years and that this is what is due to the workers. In fact, they will probably not allow you to change it even now.
The PF and ESIC will also not agree to give a refund. It is money paid, credited to the accounts, etc. I consider it an impossible event.
Regards.