According to the time stamp, this episode takes place in late June. It seems rather odd that both Agent Dales and Agent Michel would be wearing long winter coats (a brown wool top coat in the case of the former) when the average late June temperature in both DC and Northern Virginia is in the mid-80s.
As well as wearing a wedding ring, Mulder is also smoking a cigarette in one scene - another possible clue to his parentage and a tidbit about his life before the series began.
2:32 visible shadow of the boom-mic moving down the wall on the upper to mid left
David can be seen wearing his actual wedding ring which is never explained in the series whether he was, as Mulder, ever married or not. See also Unusual Suspects where he also wears his ring. He seems to be making a point in both episodes to show his ring.
Agent Michel: They're not going to find him Artie. Open it up.
(Agent Dales opens an envelope containing photographs of a dead man in a police cell)
Agent Dales: It's Skur.
Agent Michel: Maybe you want to change your description of the suspect who assaulted you.
Agent Dales: When were these taken?
Agent Michel: Last night. Two hours before you say Skur attacked you. (Agent Dales looks at Agent Michel in shock) You had a few. You were feeling bad about what happened. It's understandable.
Agent Dales: I... I didn't have that much to drink.
Agent Michel: Just leave Skur's name out of your report. Nobody else has to know.
Agent Dales: I already filed my report, an hour ago.
Special Assistant Roy Cohn: We are fighting a powerful enemy in a war of ideology. In any war there are secrets, truths that must be kept from the public in order to serve the greater good.
Agent Dales: You want me to amend my report? Take out any reference to Edward Skur? I don't understand?
Special Assistant Roy Cohn: You're not supposed to understand. You're supposed to follow orders.
Arthur Dales: (voiceover) I didn't know what I should say to her. 'I'm sorry about your loss, Mrs Skur. If there's anything I can do.' The words sounded hollow. No matter what I said, I was the man who'd busted her husband, turned her life upside down. I sat there for over an hour, trying to find my courage in a bottle. An then... then I saw someone I shouldn't... I couldn't have seen. Now it was my life that would be turned upside down.
Dorothy Bahnsen: It's in an X-file.
Dales: An X-file?
Dorothy Bahnsen: Yes. Unsolved cases. I file them under "X".
Dales: Why don't you file them under "U" for "unsolved"?
Dorothy Bahnsen: That's what I did until I ran out of room. There's plenty of room in the "Xs".
Dales: Who decides when a case gets an "X"?
Dorothy Bahnsen: The Director's office. It's...It's kind of a dead end. No one's supposed to see them but it makes for interesting reading.
Dales: Do you know what an... X-File is?
Mulder: It's uh... yeah, it's an unsolved case.
Dales: No. It's a case that's been designated... unsolved.
In the scene where Dales is being interviewed by Cohn, Cohn's assistant stands at the back of the office and silently observes. He stands in a similar pose and behaves in a similar manner to that of the Cigarette Smoking Man during Scully's initial interview in the pilot episode. The assistant, who is never named in dialogue or in the credits, is definitely an associate of Bill Mulder at the time. Despite the fact that he was not seen smoking in this episode, is it possible that Cohn's assistant was in fact the CSM?
The character of Arthur Dales would return a few times during the show's 6th season.
Agent Hayes Michel was named after the, then, fiancé of Mary Astadourian, Chris Carter's executive assistant.
The song that plays in the German doctor's house was "Lili Marlene", a song popular with soldiers of both sides in World War II.
David Fredericks reprises his role as J. Edgar Hoover from "Musings of a Cigarette-Smoking Man".
"Fellow Travelers" were Americans who were sympathetic toward the Communist cause during the Cold War, as mentioned in the senate hearing watched by young Agent Dales.
J. Edgar Hoover's paranoid rant to Arthur Dales about the Communist menace was taken almost verbatim from a speech given by Senator McCarthy.
The absence of Scully and the limited screen time of Mulder were due to David and Gillian doing reshoots for the X-Files movie in LA.
McGavin is, indeed, something of a "father" to the X-Files having played intrepid reporter Carl Kolchak in two TV movies and a one season show, Kolchak: The Night Stalker, an acknowledged influence for Chris Carter, when creating The X-Files.
Darren McGavin was originally spearheaded by Chris Carter to portray Agent Mulder's father during season 2, but scheduling problems didn't allow it.
Name: Arthur Dales
Not a 'Cultural' reference as such, but writers Frank Spotnitz and John Shiban had a teacher at the American Film Institute named Howard Dimsdale. Dimsdale, who was "black listed" during the McCarthy era, used the pseudonym "Arthur Dales" so he could continue to publish his works. This episode and its main character was a sort-of tribute to him.