Norway used to have all the tax return information public through the internet. It's still available publicly to Norwegian taxpayers through a login, but now the person you're looking up knows who viewed their details.
A sibling comment clarified Norway, but I'd like to add a caveat to that. Tax records don't necessarily tell you enough to be able to deduce the compensation package. It only shows the total. You could have switched jobs in june, there's likely no way to tell.
