Air Force One landed at Love Field, and the limo left from there. This film allegedly shows the Secret Service Agent in Charge, Emory Roberts, ordering the agents who were supposed to ride on the back of the limo to stay behind.
3 minutes. Link to Video
I didn’t look extremely hard, but I didn’t find any explanation from Roberts. However, I did find an interesting transcript of his testimony, and this, this, and all of these from Vincent Palamara who seems to have looked into this a little.
