We cannot.
Were you present when Jesus was taken down from the cross?
We were not.
You cannot tell, then, whether he was dead when taken down.
We have no personal knowledge.
Were you present when he was buried?
We were not, because we were in hiding for our lives.
You do not know, therefore, whether he was actually buried, or where he was buried.
We do not.
Were any of you present when Jesus came forth from the grave?