Roger Livesey did not receive an Oscar nomination for portraying Dr. Frank Reeves in A Matter of Life and Death.
Livesey technically does not do too much in his early scenes other than observe Peter and offer some exposition here and there of what he believes it might. Well that's apparently more than enough for Livesey since he infuses so much into the role of doctor. Livesey's has such a tremendous presence and brings such a palatable authority to his words. There is this dramatic determination that Livesey has that brings weight to Peter's situation with such ease when the doctor does start to give his own diagnosis on Peter's problem. Livesey's portrayal of the doctor is not some excessively serious performance and he equally excels in his reactionary moments. Livesey is excellent in beginning a certain casual curiosity as the doctor seems somewhat bemused by Peter's claims, but he effectively transforms this to genuine concern as it becomes abundantly clear that no matter what is the truth it's not good for Peter's well being.
Livesey's best scene though takes places in the court of the most high as he defends Peter's right to stay and lie a much longer life then what was intended for him. The doctor must defend Peter against the bitter prosecution of one Abraham Farlan (Raymond Massey) who hates all things English since he was the first casualty of the American Revolution. Livesey and Massey's face off is one of the best highlights of the film. Massey brings his usual dignified manner in his character's fairly petty points made against Peter. Livesey is terrific in this scene carrying himself in such a clever fashion actually. I like how both he and Massey bring a very different kind of passion to each of their characters. With Massey's being a venomous side of things while Livesey keeps the doctor points as spoken in a lighthearted yet still very forceful manner. Livesey portrays it as if the doctor is shooting down Abraham's points by turning them into a bit of a joke.
Livesey makes the most out of every single moment of speechifying in the heavenly court. Livesey never let's this become at all boring instead he makes his tradeoff with Massey surprisingly thrilling. Livesey's performance even manages through his delivery to give weight to the idea of the central romance even though the central romance ends up not even being anything that special past their first scene. This is a strong performance by Roger Livesey as he steals the film right out from under David Niven, although he does not do this in the way you might expect. He does not go for any sort of obvious flamboyant overacting nor does he make an overt attempts to bring needless attention to himself. Livesey very effortlessly just makes the doctor the most watchable character in the film, and the one who simply enlivens the story the most.