Conspiracy Theory
Saul is described as יושב בגבעה…ברמה, which may simply be a place description, but was seen by חז״ל as a hint to Saul’s ingratitude: he owes his position to Samuel, who dwelt in רמה:
The depths of Saul’s paranoia can hardly be overstated. He is accusing all of his advisors and relatives (בני ימיני) of betraying him for promises of reward when David is king, and that they don’t even feel bad (אין חלה מכם עלי) about doing it. And it’s not even logical: he says none of them told him about Jonathan’s loyalty to David, but he was clearly aware of it (שמואל א כ:ל): הלוא ידעתי כי בחר אתה לבן ישי, לבשתך. Note also Saul’s habit of speaking disparagingly of his enemies by referring to them by patronymic: בן ישי.
וְלַמַּלְשִׁינִים אַל תְּהִי תִקְוָה
Doeg was previously called (שמואל א כא:ח): אביר הרעים אשר לשאול, but here he is נצב על עבדי שאול which has the implication of being subservient (note וכל עבדיו נצבים עליו in the previous paragraph, and (בראשית יח:ח) והוא עמד עליהם תחת העץ, ויאכלו by אברהם). However, Samuel is also described as נצב over his students (שמואל א יט:כ) ושמואל עמד נצב עליהם. So is Doeg lording over the rest of Saul’s council or serving them? I think the ambiguity is intentional; we have a glimpse of the court politics and the jockeying for influence, and Doeg’s comments serves to push himself up the hierarchy a little more.
Ginsburg (Legends of the Jews, IV:74) mentions a tradition that Doeg was one of Saul’s oldest servants, from before he ever became king, and that is hinted at when Saul goes to look for his father’s donkeys:
Doeg’s slander is subtle; he doesn’t technically lie, but he presents the facts slightly out of order and in such a way that it make אחימלך a willing conspirator with David:
Doeg leaves out אחימלך's reticence in dealing with David, and emphasizes the fact that אחימלך “שאל לו בה׳”. We interpreted the phrase אחרי האפוד when אחימלך gave David Goliath’s sword as meaning “after consulting the אפוד and the אורים ותומים”. Here Doeg makes it seem part of the conspiracy, and is proof that David is trying to take the kingship from Saul:
The very fact that אחימלך consults with the אורים ותומים on David’s behalf is proof that he considers David a king.
Interrogation
Saul refers to the כהן גדול as בן אחיטוב; again, the patronymic is a way of being disparaging. He doesn’t even listen to אחימלך's defense that he had no reason to doubt David’s claim that he was working under Saul’s orders; David has evidently come often to consult with the אורים ותומים. The only bright spot is the fact that Saul’s servants refuse to obey orders and will not massacre the כהנים of נב.
Disobeying the king is a capital crime. רש״י points out that we learn this from יהושע:
But the halacha is very clear from this very pasuk, that we cannot use “I was just following orders” as an excuse: