The four shells found at the scene (two by Benavides, one by each of the Davis sisters) were designated Q-74, Q-75, Q-76 and Q-77 by the FBI.
At the Tippit scene, Officer Joe Poe was approached by Domingo Benavides. Benavides said that he saw the cop-killer discard some shells and that Benavides picked them up by placing in a Winston cigarette wrapper. Benavides brought this Winston wrapper, with two shells in it, to Poe.
When Sergeant Gerald Hill arrived at the scene, Poe offered the shells to him. Hill told Poe that he should keep them, to minimize the chain of possession. Hill told Poe to be sure to mark them and then give them members of the crime lab when they arrived.
After receiving the news that the possible suspect was inside the Texas Theater, many of the officers at the Tippit scene raced off for the theater. Poe remained behind with Detective Jim Leavelle and a handful of others.
Poe showed Leavelle the two spent shells that had been recovered at the scene and asked Leavelle if he wanted them. Leavelle told Poe to give them to Sergeant Pete Barnes, who was the crime lab officer at the scene. Leavelle declined taking possession of the shells in order to minimize the chain of possession.
Before leaving the scene, Poe turned the two shells over to crime lab Sergeant Barnes.
Now, here's where it gets interesting.
In April of 1964, the Warren Commission asked Poe and Barnes to identify the two shells they had handled at the Tippit scene.
Poe, when asked by the Warren Commission if he had marked the shells, replied "I couldn't swear to it. No sir." Poe then stated that he may have marked the shells but that his marking was hard to read. Poe identified the two shells (designated by the FBI as Q-75 and Q-77) as the two shells that he gave to Barnes.
However, Barnes identified Q-74 and Q-75 as the two shells that he received from Poe.
In June of 1964 the Warren Commission asked the FBI to interview Poe and Barnes again, in an attempt to address the differences. This time, Barnes told the FBI that the two shells given to him by Poe were Q-74 and Q-77 (as opposed to Q-74 and Q-75, as he told the Commission back in April). Poe told the FBI, after studying all four of the shells, that he couldn't find his mark on any of them and therefore, he could not positively identify any of the shells as being the same ones that he had received from Benavides.
So, we have Poe's reluctance to swear that he marked the shells. We also have a lack of Poe's identifiable mark in any of the four shells.
In 1996, Jim Leavelle told Dale Myers that Poe did not mark the shells. Leavelle said "Poe did not mark them. There was no reason to mark them. There is an evidence bag that is marked with the offense number along with your initials. The evidence goes to the crime lab where it is checked and returned to the bag and kept there until trial."
Leavelle said that Poe was afraid that he would get in trouble for failing to mark the evidence. This would explain why Poe said that he may have marked the shells but couldn't find his markings because the shells were difficult to read. Poe said that the shells had been obliterated with markings by himself, the Crime Scene Search Section, The FBI, etc.
In reality, the shells were not "obliterated" with markings at all.
Leavelle goes on to tell Myers "Sometimes, officers think they are doing the right thing and get in over their heads. But, I talked to Poe. He said that he didn't remember marking them. But, that is something we didn't do back then. I didn't do it. He didn't do it. I didn't ask him to do it. When I was out there and Poe offered the shells to me, I said no, just go ahead and put them in the envelope and send them on to the crime lab and let them work with them from there."
Crime lab Lieutenant J.C. Day confirmed that the 1963 Dallas Police Department did not have a consistent policy regarding the marking of evidence. Much of the ballistic evidence in the Kennedy assassination was marked by the Crime Scene Search Section, but some was not. There was a lack of consistency.
Shortly after Benavides handed the two shells over to Poe, crime lab Sergeant Barnes arrived at the scene and began collecting evidence. Crime lab senior officer Captain George Doughty was with him. Remember, Poe first offered the shells to Leavelle, who declined and told Poe to turn the shells over to the crime lab. To me, it is very reasonable that Poe simply did not mark the shells in light of the crime lab's presence at Tenth and Patton.
Both Doughty and Detective Dhority both selected Q-74 and Q-77 as the two shells they had handled.
