Thanks, Lisa @ the Eva Perry Mock Newbery Club, for alerting us to the fact that The Graveyard Book might be ineligible after all, as one chapter ("The Witch’s Headstone") was included in Gaiman’s M is for Magic last year. I’ve placed a hold on that book so that I can compare the previously published version to the current one.
Even if only a portion of a book has been previously published, that can indeed disqualify it under the "published in the preceeding year" and "original work" definitions of the the Terms. An eligibility question like this would be resolved between the committee Chair and the Priority Group Consultant (an appointed position in ALSC, who acts as support for all the award committee chairs, and is their line of communication to the ALSC leadership should that be necessary. Occasionally, tricky eligibility questions will get a final ruling from the Executive Committee, in consultation with the Chair and Priority Group Consultant.) In resolving this particular type of eligibility question, generally the "previously published" material in question will be closely scrutinized for comparison with the current version, to try and determine if this is the "same" work. It’s common for fiction writers to develop short stories into novels; sometimes the original versions are left intact, nearly word for word, and sometimes they are completely rewritten, with only a character or plot thread remaining intact.
Because each possible eligibility question is handled on a case by case basis within the committee, and because that work falls under the "confidentiality" clause of the committee, we can’t get a definitive answer on this particular book from the actual committee. But Sharon and I may decide not to use it for our Mock Discussion. We’ll see.