In the dictionary:
Dead: no longer alive
Her mother had been dead for ten years.
Her parents were long dead.
The man was already dead
So, what is the difference between "He is dead" & "He was dead"?
If we choose other adjective "nice" for example, then it is so easy
He is nice: At this moment he is nice
He was nice: He was nice in the past but we don't know if he is nice now
But: He is dead: At this moment he is no longer alive, but when he is dead, that event was already in the past even if it only happens a few seconds ago
Or we can say "He has just been dead" seems accurate
He was dead: He is no longer alive in the past.
When to use "He is dead" and when to use "He was dead"?
Best Answer
English narrative normally uses the past tense, even to describe ongoing action:
Otherwise, in everyday conversation or dialogue, use the present tense.