FIDE was once not careful enough...

(6+11) White to move, mate in 2.

Harri Hurme, presumably 1991

There's a reason why I don't post this in More Puzzles forum...

Hint 1: [The title and the year of "publication" are helpful. Unfortunately, I haven't found any online resource to help with this.]

Hint 2: [Back in 1988, FIDE's laws of chess, Rule 9.1, states "the king is said to be in check, when the square it stands on, is threatened by one or two pieces of the opponent".]

Define "threatened" - bRd2 is pinned and may or may not "threaten" h2.

I think FIDE didn't define it at that time (and now as well), but taking the usual definition, bRd2 threatens h2 in the meaning of the opposing king cannot move to h2 (if there's no wQg2).

FIDE instead defines in the glossary (1 July 2014) "attack: 3.1. A piece is said to attack an opponent’s piece if the player’s piece can make a capture on that square."

...alongside 1.2: "[objective is to] place the opponent's king 'under attack' in such a way that the opponent has no legal move."

And later in 1.2: "[...] and also 'capturing' the opponent's king are not allowed."

=> one cannot attack a king since one cannot capture a king?

This is why people make these silly problems. [1. Kh2! ^2. Kg1#; 1...Nf3+ 2. Qxg6#!!; 1...Ng4+ 2. Qh3#!!]

Correct solution.

And apparently FIDE is still not careful enough (a pinned piece doesn't attack anything according to that definition, and yours as well for king not attacked by anything).