I'm working on a murder mystery arc. My PCs have been summoned for jury duty in a city where they are staying, which basically requires them to investigate the death of a local noble and find the evidence to prove whodunnit.
Now there are lots of clues and plenty of blame to go around. Essentially, all 6 surviving members of the local ruling council are suspect, and each one had a small part in the overall plot. I'm trying not to railroad a solution; if the PCs settle on only one suspect, they might successfully pin the whole thing on them, or even pin it on a low-level thug as the actual shooter, without exposing the conspiracy behind it.
Here's my conundrum: as the final level of conspiracy, I had in mind that the victim himself was the mastermind behind the whole plot. He orchestrated all of the council to cooperate in his assassination, intending to discredit all, then return himself. He's currently lying in Gentle Repose, with the 10-day limit on that spell as the ticking clock for the PCs' investigation. HIS intention would be to have all the council members implicated before returning via Reincarnate, so he could take full control without being recognized as his former self.
The Twist is that I intend to give the party a single access to Speak With Dead, ostensibly so they can talk to the Captain of the Guard about the assassination. The Captain was severely punished for his failure to protect Lord Kadav'rr, but we have already established that the crows ate his tongue before his passing. Not a good subject for Speak With Dead. I expect that the PCs will have the idea they can speak with the slain noble instead.
My intention is that the Speak With Dead and Reincarnate conflict, because they work on a similar mechanism -- recalling the person's essence to the/another body. SWD explicitly says that you cannot recall the person again within 10 days and Reincarnate is only good up to 10 days (Yes, I know Gentle Repose extends that timeline; but the timing isn't the issue).
After a more careful reading of the spells, RAW it doesn't look like there is a necessary conflict. Speak says it recalls the "animating spirit" not the soul; Reincarnate attaches the soul to another body. So just on that, it looks like you could speak with a dead person and then reincarnate them, based on the difference between Spirit and Soul. (BTW, IRL cleric here and I can't define the difference between spirit and soul).
But I don't wanna do that! I want the conflict where speaking with him foils his plan to reincarnate. Is there a way to interpret these spells as mutually exclusive without just DM hand-waving? My party does not have a tendency to rules lawyer, so it may not be an issue, but I want to be prepared. Can anyone suggest a more cogent answer than "it's a modified version of the spell that just works that way"?
Thank you!