the polish law says that you must have an accountant.
But what if you're already an accountant, do you have to get another accountant? And does that accountant have to get another and another? Maybe that's why Poland is flooded with accountants.
Just messin, you don't need an accountant, if you have a calculator and can understand the tax returns form (which nobody can, seeing as it's written in that strange formal Polish) then you can do it yourself.