For example, Kara the Fighter foolishly ran 90' ahead of her party and has just been stabbed to death by a goblin. Her body has some stab wounds but is otherwise fully intact. The party cleric can't reach Kara on his turn. He has True Resurrection prepared and has the material components. Would he able to use True Resurrection to bring Kara back to life, at that moment?
For reference, the description of true resurrection states:
You touch a creature that has been dead for no longer than 200 years and that died for any reason except old age. If the creature's soul is free and willing, the creature is restored to life with all its hit points.
This spell closes all wounds, neutralizes any poison, cures all diseases, and lifts any curses affecting the creature when it died. The spell replaces damaged or missing organs and limbs. If the creature was undead, it is restored to its non-undead form.
The spell can even provide a new body if the original no longer exists, in which case you must speak the creature's name. The creature then appears in an unoccupied space you choose within 10 feet of you.
Best Answer
He cannot cast the spell if the conditions for its casting aren't met.
This is distinct from him casting the spell and the spell failing, mind you. In order to cast the spell, he must be within the range specified by the spell, which in this case is touch. Now there is an exception to this in this spell, which applies if the body no longer exists. Given that the body is still in existence, I would say that the spell fails should he decide to try and cast it regardless but that the spell slot is not consumed. The reasoning behind this is that the range of the spell is part of its requirements for its casting, as much as any component, so casting True Resurrection without being in range would have the same result as casting it without a diamond: the process of casting it remains incomplete.
That said, if you are using the optional rule on Xanathar's Guide to Everything (p. 86), under "Invalid Spell Targets", the spell slot would be expended:
That said, any high-level cleric would be aware of this, and would most likely not cast the spell.