A family murder in Great Smials?

[Inziladun]

I have no particular qualm about debating side issues, at least until the thread starter becomes irate about it.

Originally Posted by Formendacil

Nonetheless, thain is not a military title but a noble title. What is more, the circumstances surrounding the appointment of the first Thain Oldbuck show that he was basically appointed with powers of Regent, not unlike the Stewards of Gondor--a parallel that shows that plenipotentary, hereditary regencies had precedent under the laws of the Dúnedain.

Maybe that was part of the Thainship when it began, but by the time of the War of the Ring it appears to be a military (though, due to the nature of the Shire and its perpetual guarding by Outsiders, a mainly ceremonial) post.

The Thain was the master of the Shire-moot, and captain of the Shire-muster and the Hobbitry-in-arms, but as muster and moot were only held in time of emergency, which no longer occurred, the Thainship had ceased to be more than a nominal dignity.

LOTR Prologue

Though the issue of Laila's death would have been a scandel, and a talking point for 99 days, I can't see it being an "emergency".
At any rate, there's no mention in the Prologue of the Thain having anything to do with law or criminal matters.