A.T. Robertson Commentary Mark 15:44

"And Pilate marvelled if he were already dead: and calling unto him the centurion, he asked him whether he had been any while dead." — Mark 15:44 (ASV)

If he were already dead (ε ηδη τεθνηκεν). Perfect active indicative with ε after a verb of wondering, a classical idiom, a kind of indirect question just as we say "I wonder if." Usually death by crucifixion was lingering. This item is only in Mark.

Whether he had been any while dead (ε παλα απεθανεν). B D read ηδη (already) again here instead of παλα (a long time). Mark does not tell the request of the Jews to Pilate that the legs of the three might be broken (John 19:31–37). Pilate wanted to make sure that Jesus was actually dead by official report.