I discuss the bullet that hit the grass near the manhole cover at length in A Comforting Lie: They Myth that a Lone Gunman Killed President Kennedy. This is a good example of real evidence that was suppressed and denied, even though the finding of a bullet in the grass was initially acknowledged and was even discussed by local newspapers, and even though a photo of the hole in the grass appeared in a local newspaper the next day.
No one has yet credibly explained what object created a visible dug-out hole in the grass. One suggestion has been the ludicrous theory that a chunk of brain tissue hit the grass.
Dallas policeman J. W. Foster, who was positioned on top of the triple underpass, saw a bullet strike the grass near the manhole cover on the south side of Elm Street, about 350 feet from the TSBD. He reported this to a superior officer and was instructed to guard the area. This is a matter of record.
The hole made by the bullet was even photographed, and the picture appeared in the Fort Worth Star-Telegram on 11/23/63.
Journalists and bystanders were kept at a distance from the spot where the bullet landed. In the photos taken of this event, i.e., the finding and removal of the bullet, we see Officer Foster and a civilian-clothed Deputy Sheriff Buddy Walthers standing over the spot where the bullet landed, along with an unidentified man in a suit. Photos show the unidentified man in a suit bending down, reaching out his left hand toward the dug-out point on the ground as if to pick up something, standing back up, apparently holding a small object in his hand, and then putting his hand in his pocket.
In his WC testimony, Officer Foster denied a bullet was recovered from the grass near the manhole cover, though he did not explain what the man in the suit picked up and put into his pocket. Foster did, however, say that a bullet "had hit the turf there at that location." Obviously, that bullet could not have been fired by the alleged lone gunman.
Walthers' widow later revealed that her husband told her a bullet was found in the grass.