In a perpetual chase dispute, does the burden of proof fall on the claimant or the accused player?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws for movement, checkmate and both repetition rulings: a side that forces a repetition by perpetual check or perpetual chase loses rather than drawing. The chase half has not been validated against the official casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it before publishing.
Direct answer
Neither, really: the recorded moves decide, not an argument. A chase is judged from the board: if one side threatened the same piece on every one of its moves, and no exception applies, that side must vary or lose. The player who raises it points the arbiter to the repetition, but the scoresheet and the position settle it, not intentions or who argues better.
Why it is a question of record
Chase is defined by what happened on the board: which piece was threatened on each move, whether it was protected, and which piece made the threat. Those are facts a scoresheet can establish, so the arbiter does not have to weigh what either player meant to do.
What a player raising it should bring
An accurate scoresheet, the recurring position, and the piece they believe was threatened on every move. Two things change the ruling: if a check appeared anywhere in the cycle, chase is not adjudicated at all, and if both sides were chasing, the repetition is a draw.
Related questions
Does the same apply to perpetual check claims?
Yes, the recorded moves decide there too. Perpetual check is simply easier to establish, since whether each move gave check can be read straight off the board.
What happens if the evidence is genuinely unclear either way?
The arbiter rules using the event's rules and the casebook of worked examples.
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