As the title says, Our party fought a beefed up ghoul that ended up killing our Cleric before we managed to kill the ghoul.

On the way to the church to resurrect our cleric he came back as a ghoul and had to be killed. (again)

Now players at the table have said that since he was an undead he can no longer be revived via the spell Raise Dead. Since the spell specifically mentions "The spell can't return an undead creature to life."

I took this to mean I couldn't use this to raise say a Vampire back to unlife but if I wanted I could raise him back as his human self AFTER we killed his undead shell.

I need some kinda official ruling as this seems to have become a topic of hot debate at our DnD table and the DM has taken a "I don't have an opinion on the matter" stance. Ultimately its the DM's call but he seems to want some kinda official ruling before he makes a call. The Cleric PC made a new character an seems to have left his Cleric to be perma dead instead of arguing about it so this doesn't matter for our campaign but I want to know for the future. When/If this comes up again.

I found this Google Searching, there was a similar post in rpg.stackexchange.

https://twitter.com/jeremyecrawford/status/709791324656902144

JC argues that if you tried to raise dead on an PC turned undead then they would return as undead, because their type has been changed.

Apparently *Resurrection* gets around this.  Personally I dislike this, because it's arguing over the "creature type" of a corpse, but meh.  I find it the less interesting more CRPG rational.

Mike Mearls seems to say it does revive them as human.

This is why I was looking for a more official/recent ruling on this.

There are no official rulings on this either way (I checked the sage advice compendium).

The 2 ways that I interpret "The spell can't return an undead creature to life" are:

• Can't return a dead undead to a "living" undead.
• Can't return a "living" undead to not undead.

The spell doesn't say that a corpse can't be resurrected as a non-undead (that is in fact the entire point of the spell), so I would allow it as a DM.

I'm with DxJxC, mostly.

I consider that "dead creature" is not a creature type (it really isn't :p ), so all relevant spells practically target corpses. Dead things that have been creatures at some point in the past.

Now, most relevant spells do not return undead - I read that as "if you target a corpse that has been undead once, the undead doesn't come back". But if the creature has once been a living entity, and that target is still within the spell's parameters, it revives the creature.

So. If a creature dies, and spends more than 1 minute as a zombie, Revivify can't help it. I will note that Revivify does not include the "not undead" clause, though, so I can see where Jeremy Crawford is coming from.

If a creature has been a vampire for 200 years, Raise Dead won't help it either. But if it has been a zombie for a week, it would still return it to (its previous) life.

The last sentence in the second paragraph of Raise Dead says, "The spell can't return an undead creature to life." Undead are not living. Undead are not dead. If you kill an undead creature it becomes dead. You still cannot raise it with the spell. You need to find a more powerful spell.

 How did the deceased PC even become a ghoul?  Was it some ability this "beefed up" ghoul had?

No idea as I was a PC so didn't have access to what the DM was using as a template but it cause him to raise as a ghoul shortly after being killed by it.

Regardless of how it happened the important part is "can you raise dead a undead back to life if you killed its undead form?"

How it happened isn't as important as is it possible to raise dead an PC that turned into an undead?

I'd say, "yes." What is important is what your DM says.

I don't think undeath was supposed to be synonymous perma-death.

Hey Hecktor, I see a zombie walkin toward us, cast that revivify spell thingy and make it not undead!

No can do Deter, it's an undead, those types of spells don't work on them.

Oh, well hold on...*kills the zombie*. Can you bring it back now?

I can try, lets see if this Raise Dead spell works...*looks at DM*

As a DM I'd consider letting it work, assuming the creature has not been dead, then undead, then dead again beyond the scope of the spell. 

I'd say do whatever is best for the story.  If the player wants to keep playing his PC then let it work as long as the original character death was less than 10 days ago.  If the player wanted to retire his PC anyway then don't let it work.  The rules are supposed to make the game fun and the DM is allowed to completely change them to keep making it fun.

Regarding the original post, the spell says it cannot return an undead creature to life. The Cleric was a ghoul when he died, so the spell is a no go.

However, if you used true resurrection it would work.

Using Raise Dead to restore a person from undeath is too simple a solution for something that should be serious. Being killed by a Wraith or Wight should not be so trivial.

I don't think anyone is questioning whether it is proper for the DM to do whatever he wants in order to make the game fun. We all agree with that. Since this is the rules forum and someone asked what the rules say, it's fair to give an accurate answer so the DM can decide to use them or not.

Another trick the DM might choose to use in this situation is for a casting of Raise Dead to be unsuccessful, but to enlighten the caster with what needs to be done to raise the character from their current predicament. In the end, if the party has to go on a quest to do the needful so that the temple priest can bring the character back to life, the actual spell that is used isn't all that important.