Lee said of the stories,
"The New York Tribune has attacked me for my treatment of your grandfather's slaves," he told his son Custis, "but I shall not reply."
"the statement is not true; but I had not thought proper to publish a contradiction."
"there is not a word of truth in it...No servant, soldier, or citizen that was ever employed by me can with truth charge me with bad treatment."
I guess without the photographs of the scars on the back of Mr. Norris (certainly if they existed the press and history would have them as their center piece of the life of R. E. Lee) the story is unproveable.