Here’s a snip from Harkness’ testimony:
Mr. BELIN - Now you mentioned that you put something on the radio here, and I hand you here what has been marked as Sawyer Deposition Exhibit A. Before doing that, do you remember what call number you used, you were using on that day?
Mr. HARKNESS - I believe 260.
Mr. BELIN - Well, I notice here that there is a call with a notation at 12:36 p.m., 260 to 531. 531 is your office in the main station?
Mr. HARKNESS - Yes, sir.
Mr. BELIN - What does it say there on that transcript?
Mr. HARKNESS - "Witness says shots came from fifth floor, Texas Book Depository store at Houston and Elm. I have him with me now and we are sealing off the building."
Mr. BELIN - All right, that was at 12:36 p.m.?
Mr. HARKNESS - Yes, sir.
Mr. BELIN - Had the building been sealed off at that time?
Mr. HARKNESS - Not to my knowledge. There were several officers around it, but I don't know whether it had been sealed off or not.
Mr. BELIN - In the process of sealing off the building, what did you do?
Mr. HARKNESS - Asked for a squad.
Mr. BELIN - How long did it take you after that to have the back part sealed off?
Mr. HARKNESS - The guard was arriving by the time I got off my motorcycle. There was already additional squads en route.
Mr. BELIN - How soon after 12:36 p.m., would you say the building was sealed off?
Mr. HARKNESS - It was sealed off then because I was back there and two other men.
Mr. BELIN - You are talking about the back part of the building?
Mr. HARKNESS - Yes, sir.
Mr. BELIN - What about the front part of the building? When was that sealed off?
Mr. HARKNESS - Inspector Sawyer and two officers were there.
Mr. BELIN - By the time you got around to the front part of the building?
Mr. HARKNESS - Yes, sir; by the time I put the witness in his car, I went immediately to the back.
Mr. BELIN - In other words, as I understand the sequence, you first went to the back of the building and had that sealed off first, or not?
Mr. HARKNESS - No, sir.
Mr. BELIN - You tell me what happened then.
Mr. HARKNESS - I had this witness with me. I didn't want to lose this witness.
Mr. BELIN - All right.
Mr. HARKNESS - So I took him to the car.
Mr. BELIN - To Inspector Sawyer's car?
Mr. HARKNESS - To Inspector Sawyer's car, which was right in front.
Mr. BELIN - Which was parked in front of the Texas School Book Depository?
Mr. HARKNESS - And left the witness there and went around to the back.
Mr. BELIN - On whose radio did you call? Did you call in before or after you left the witness in the car?
Mr. HARKNESS - I don't remember in exact sequence there, but it was in the process of going to the car there.
Mr. BELIN - Then what did you do?
Mr. HARKNESS - See, here is the thing. The radio traffic was heavy at the time, and it depended on how long you had to wait to get in.
Mr. BELIN - All right, in any event, after you made the call, what did you do on the radio? And after you got the man in the car?
Mr. HARKNESS - Well---
Mr. BELIN - The witness in the car, what did you do?
Mr. HARKNESS - Stayed at the back of the building until I was relieved by a squad.
Mr. BELIN - So you then went to the back of the building?
Mr. HARKNESS - Yes.
Mr. BELIN - When you were at Inspector Sawyer's car, did you see him there?
Mr. HARKNESS - Yes, sir.
Mr. BELIN - Was he at his car?
Mr. HARKNESS - Yes, sir; he was by his car, near his car.
Mr. BELIN - Do you know whether or not he had gone inside the building.
Mr. HARKNESS - No, sir.
Mr. BELIN - You mean you don't know?
Mr. HARKNESS - Don't know whether he had gone in or not. Actually, he was standing there in front taking information. All the information was being funneled to Inspector Sawyer.
Mr. BELIN - Did you tell him you had a witness?
Mr. HARKNESS - Yes, sir.
Mr. BELIN - In his car?
Mr. HARKNESS - Yes, sir.
Mr. BELIN - At that time, had the building been sealed off yet when you told him that?
Mr. HARKNESS - At that time?
Mr. BELIN - When you told Inspector Sawyer that you had a witness that said the shot came from the building, up to that particular moment, had the front part of the building been sealed off yet?
Mr. HARKNESS - Yes, sir.
Mr. BELIN - It had already been sealed off?
Mr. HARKNESS - There was two officers with Inspector Sawyer at the front.
Mr. BELIN - Were they stopping people from going in and out?
Mr. HARKNESS - I don't know.
Mr. BELIN - You don't know?
Mr. HARKNESS - No, sir; I don't know that, because I didn't go up and talk to them.
Mr. BELIN - Did you notice whether or not people were coming in and out of the building?
Mr. HARKNESS - No. I was interested in getting around to the back of the building to make sure it was.
Mr. BELIN - Then am I correct that your testimony is that you didn't notice whether people were coming in and out? Did you notice, or did you not notice whether people were coming out of the building at that time?
Mr. HARKNESS - Several officers at the area, and it was a lot of people around. I don't know whether they were going in or out or not. I couldn't say that.
Mr. BELIN - Then you went around to the back of the building?
Mr. HARKNESS - Yes, sir.
Mr. BELIN - Was anyone around in the back when you got there?
Mr. HARKNESS - There were some Secret Service agents there. I didn't get them identified. They told me they were Secret Service.
Mr. BELIN - Then did you say around the back of the building?
Mr. HARKNESS - Yes; I stayed at the back until the squad got there.
Mr. BELIN - Then what did you do?
Mr. HARKNESS - I went back to the front, and Inspector Sawyer---helped get the crowd back first, and then Inspector Sawyer assigned me to some freight cars that were leaving out of the yard, to go down and search all freight cars that were leaving the yard.
Harkness is identified in that image that Dan posted. Based on the sequence that Harkness says happened, it suggests to me that this image was taken shortly after 12:36.