Laws of chess query

Discuss anything you like about chess related matters in this forum.
Post Reply
Paul Habershon
Posts: 699
Joined: Sat Aug 07, 2010 5:51 pm

Laws of chess query

Post by Paul Habershon » Sat Jan 25, 2025 4:58 pm

Players discover that a game agreed drawn the previous day contained an illegal move near the end. The player in check did not escape the check (though it wasn't mate) and his opponent then played a move which enabled the 'dead' king to move out of check, so neither player noticed the irregularity.

Common sense suggests that the agreed draw stands but my question is: Which FIDE law expressly covers this situation?

Alex McFarlane
Posts: 1864
Joined: Sat Aug 02, 2008 8:52 pm

Re: Laws of chess query

Post by Alex McFarlane » Sat Jan 25, 2025 5:13 pm

7.5.1 which states that corrections can only be made during the game.
"An illegal move is completed once the player has pressed his/her clock. If during
a game it is found that an illegal move has been completed, the position
immediately before the irregularity shall be reinstated. If the position
immediately before the irregularity cannot be determined, the game shall
continue from the last identifiable position prior to the irregularity. Articles 4.3
and 4.7 apply to the move replacing the illegal move. The game shall then
continue from this reinstated position."

Paul Habershon
Posts: 699
Joined: Sat Aug 07, 2010 5:51 pm

Re: Laws of chess query

Post by Paul Habershon » Sat Jan 25, 2025 5:44 pm

Alex McFarlane wrote: ↑
Sat Jan 25, 2025 5:13 pm
7.5.1 which states that corrections can only be made during the game.
"An illegal move is completed once the player has pressed his/her clock. If during
a game it is found that an illegal move has been completed, the position
immediately before the irregularity shall be reinstated. If the position
immediately before the irregularity cannot be determined, the game shall
continue from the last identifiable position prior to the irregularity. Articles 4.3
and 4.7 apply to the move replacing the illegal move. The game shall then
continue from this reinstated position."
Thanks, Alex. My online searches of Law 7.5.1 omit your crucial first line: '... corrections can only be made during the game...'

The nearest I could find was 8.7 on recording moves:
'At the conclusion of the game both players shall sign both scoresheets, indicating the result of the game. Even if incorrect, this result shall stand, unless the arbiter decides otherwise.'

This law seemed to apply to score sheets rather than specifically illegal moves

Roger Lancaster
Posts: 2059
Joined: Tue Mar 17, 2015 2:44 pm

Re: Laws of chess query

Post by Roger Lancaster » Sun Feb 02, 2025 1:05 pm

Separate query to which I've since found the answer (Law 4.3.3) but which had me stumped at the time and may stump others. White king on e1, pawns on e5 and c5. Black rook on e8, knight on d6, king irrelevant. White tries to play e5xd6 which is illegal due to the pin. Having touched both the e5 and d6 pieces more or less simultaneously, is he obliged to make (a) the only legal pawn move, e5-e6, or (b) the only legal capture, c5xd6 ?

NickFaulks
Posts: 9315
Joined: Sat Jan 02, 2010 1:28 pm

Re: Laws of chess query

Post by NickFaulks » Sun Feb 02, 2025 1:51 pm

Alex McFarlane wrote: ↑
Sat Jan 25, 2025 5:13 pm
7.5.1 which states that corrections can only be made during the game.
In this case, but not universally.

An arbiter for whom I have great respect told me that he had once rejected a repetition claim because the position had appeared only twice, and the claimant went on to lose. Later that evening ( at his own instigation ) he had played through the game and discovered an earlier occurrence, so he changed the result to a draw.

This surprised me, and I don't think I like it, but I assume he was correct to do so.
If you want a picture of the future, imagine a QR code stamped on a human face — forever.

User avatar
IM Jack Rudd
Posts: 5183
Joined: Tue Apr 17, 2007 1:13 am
Location: Bideford
Contact:

Re: Laws of chess query

Post by IM Jack Rudd » Sun Feb 02, 2025 2:08 pm

The answer to Roger's query is that if white touched the knight first, he must play cxd6. If he touched the pawn first, or we don't know which he touched first, he must play e6.

Alex McFarlane
Posts: 1864
Joined: Sat Aug 02, 2008 8:52 pm

Re: Laws of chess query

Post by Alex McFarlane » Sun Feb 02, 2025 3:33 pm

NickFaulks wrote: ↑
Sun Feb 02, 2025 1:51 pm
Alex McFarlane wrote: ↑
Sat Jan 25, 2025 5:13 pm
7.5.1 which states that corrections can only be made during the game.
In this case, but not universally.

An arbiter for whom I have great respect told me that he had once rejected a repetition claim because the position had appeared only twice, and the claimant went on to lose. Later that evening ( at his own instigation ) he had played through the game and discovered an earlier occurrence, so he changed the result to a draw.

This surprised me, and I don't think I like it, but I assume he was correct to do so.
I will resist asking if there is such an arbiter :roll:
The game ended with the correct repetition claim. Everything that happened after that was not part of the game. The arbiter acted correctly in rectifying a mistake that was made by him/her.

There was a fairly recent 4NCL Congress which had a similar situation. In that case it was the Chief Arbiter who overturned the original arbiter's decision several hours later. That decision was backed by the Appeal Committee.

Paul Cooksey
Posts: 2044
Joined: Fri Oct 21, 2016 4:15 pm

Re: Laws of chess query

Post by Paul Cooksey » Sun Feb 02, 2025 3:36 pm

An arbiter wrongly denied my claim of a win on time in a weekend congress in 1993. Can I get the result changed?

Tim Spanton
Posts: 1405
Joined: Thu May 01, 2008 11:35 am
Contact:

Re: Laws of chess query

Post by Tim Spanton » Sun Feb 02, 2025 4:19 pm

Paul Cooksey wrote: ↑
Sun Feb 02, 2025 3:36 pm
An arbiter wrongly denied my claim of a win on time in a weekend congress in 1993. Can I get the result changed?
Sorry - you're out of time

Roger Lancaster
Posts: 2059
Joined: Tue Mar 17, 2015 2:44 pm

Re: Laws of chess query

Post by Roger Lancaster » Sun Feb 02, 2025 4:43 pm

IM Jack Rudd wrote: ↑
Sun Feb 02, 2025 2:08 pm
The answer to Roger's query is that if white touched the knight first, he must play cxd6. If he touched the pawn first, or we don't know which he touched first, he must play e6.
That's correct, of course, Jack. I'm not a qualified arbiter but I'm tolerably well-acquainted with the FIDE Laws. Even so, if the situation had arisen in practice where the pieces were touched more or less simultaneously, meaning that it was impossible to judge which was touched first, I wouldn't have given myself (in a situation with no qualified arbiter present) a better than 50/50 chance of making the correct decision. I hesitate to say this but I've come across one or two (that's probably a euphemism!) qualified arbiters whose chances I wouldn't rate as significantly better.

Paul Cooksey
Posts: 2044
Joined: Fri Oct 21, 2016 4:15 pm

Re: Laws of chess query

Post by Paul Cooksey » Sun Feb 02, 2025 6:43 pm

Tim Spanton wrote: ↑
Sun Feb 02, 2025 4:19 pm
Paul Cooksey wrote: ↑
Sun Feb 02, 2025 3:36 pm
An arbiter wrongly denied my claim of a win on time in a weekend congress in 1993. Can I get the result changed?
Sorry - you're out of time
I guessed I was. But not when I signed the scoresheet apparently. At the end of the event?

James Plaskett
Posts: 362
Joined: Wed Mar 04, 2009 10:36 pm

Re: Laws of chess query

Post by James Plaskett » Thu Mar 20, 2025 8:02 pm

David Goodman and I drew a Benko Gambit at the London Evening Standard Open of 1976... to afterwards realise that a position had arisen where BOTH kings were in check!

Kevin Thurlow
Posts: 6671
Joined: Wed Apr 30, 2008 12:28 pm

Re: Laws of chess query

Post by Kevin Thurlow » Thu Mar 20, 2025 10:04 pm

"David Goodman and I drew a Benko Gambit at the London Evening Standard Open of 1976"

Didn't he hate the Benko? I assume you were tormenting him...

Post Reply