When Josh and Senator Haynes are talking in the beginning of the episode, the Senator goes to leave his office. Senator Hoynes is from Texas, but the state flag at the entrance to his office is from Tennessee.
During Josh's flashback, the camera pans across President Bartlet's campaign headquarters. A sticker reading "Bartlett Hoynes" is visible on the side of one of the monitors. This sticker would not have been printed yet, as Hoynes is still the principal opponent for Bartlet in the race and has not yet been added to the ticket as VP.
The controversy regarding the 25th Amendment and who was "in charge" while the President was in surgery surrounds the failure of the President to sign a letter transferring power to the Vice President. The 25th Amendment also provides that the Cabinet may determine that the President is unable to discharge the duties of his office and transfer power to the VP without this letter. Before being anesthetized, the President instructs Leo to assemble the Cabinet. The entire premise that nobody was "in charge" is false.
As Sen. Hoynes is leaving his office to go vote, a Tennessee state flag is visible to the right of the entrance to his office suite. Hoynes was a senator from Texas.
Josh is unloaded from the ambulance head first. Patients are always placed in an ambulance so that their head is closer to the front, and would therefore come out feet first.
The conversation between Abbey and the surgeon who operates on Bartlet is medical gibberish. She first asks him about Bartlet's PO2, which is a measure of the dissolved oxygen in his blood. She has no reason to ask this because Bartlet is not in respiratory distress. She then asks the surgeon if he is going to do a "laparoscopy." "Laparoscopy" is just a generic term for surgery that is done using small incisions and fiber optic cameras. She is probably referring to a "laparotomy," which is an operation done to look for abdominal bleeding and injury to abdominal organs. The surgeon responds that he will do this surgery because "we want to make sure the peritoneum is intact." This is the wrong reason to do a laparotomy. The peritoneum is the tissue lining the organs in the abdomen and to do a laparotomy, incisions have to be made through it. Hence it is self-defeating to do a laparotomy to "make sure the peritoneum is intact."
During the trauma scene, it's unlikely that the E.R. staff would let Josh remain without oxygen (he pulls the mask off his face himself.) He goes without oxygen for about 20 seconds in the scene. There are at least eight emergency personnel around, and you can hear a paramedic say that his 02 saturation is 94% on 15 liters. Josh is coming in with a collapsed lung secondary to a GSW (gun shot wound,) which means high-flow 02 at all times. In reality, no way would emergency staff let him go without it that long.
When the Secret Service busts in on the VP receiving the USC volleyball jersey, the press flashes reveal the blue backdrop only a couple feet beyond the patio doors.
In the DVD commentary it mentions that, during the original airing, Janel Moloney's named was misspelled. It was corrected in future airings and on the DVD release.
In a flashback scene, Josh uses a Verizon pay phone. Verizon didn't exist at the time that the flashback was taking place.
It's mentioned that the gunmen were part of West Virginia White Pride, and discovered just outside Blacksburg. There is no Blacksburg in West Virginia. However, just because the men were members of a West Virginia based organization doesn't mean they were found in West Virginia.
After discovering that the President has been shot, the secret service rush to secure the Vice President, who is meeting with the USC women's softball team. But the President was shot after 10 p.m., and the visit with the Vice President would not be scheduled for that late in the day.
When Margaret is talking with Mrs Landingham she hurriedly puts on the TV before it displays anything about the shooting. The screen merely shows a "special report" which could have been anything.
A flashback scene shows Jed Bartlet campaigning in a sparsely-populated VFW in New Hampshire. As a scandal-free (former/current) governor and state legislator of that same state, it is highly unlikely so few people would be in attendance for a campaign event.
When Margaret and Mrs. Landingham are talking (before they learn the President has been shot), Mrs. Landingham says she recalls a time a time at the "Governor's mansion. It was about ten years ago...More. Maybe 12." Except 10-12 years prior to that moment, Bartlet was not governor; he was a member of the U.S. House of Representatives.
The news reader for the special TV report on the President's shooting, as seen on TV in the White House by Mrs. Landingham and Margaret, mispronounces the shooting location, Rosslyn, Virginia. He says "ross lin" as if he had never heard of it. It is the current or former home of one of the three D.C. network TV stations, the Gannett publishing company, USA Today, and the Newseum, among others. Any local or network news anchor would know that it is pronounced 'Rosslyn /rozlin/.
In his Q&A at the Nashua VFW, then-Governor Bartlett, a lifetime native of New Hampshire, mispronounces its capital, "Concord". He says "Concorde" (like the jet) rather than the traditional New England pronunciation, "Concerd" (homophone to the word "Conquered").
When the Secret Service is rushing Abby to the hospital and agent refers to her as "Mrs Bartlett". She should be "Dr Bartlett".