Arthur O'Connell received his second and final Oscar nomination for portraying Parnell Emmett McCarthy in Anatomy of a Murder.
O'Connell is absolutely appropriate for the role though without his not quite fatherly, but sort of elderly knowledge and warmth in equal quantities. O'Connell stay low key throughout the film never trying to stealing a scene from Stewart, but nor should he since he is suppose to be supporting Stewart first and foremost. O'Connell never attempts to take the spotlight in the film but does manage to show you can most certainly serve the film even if one is always more content to be around it.
O'Connell has a good chemistry with Stewart in all of their scenes together. They are natural and their is a certain warmness between them that work quite well, without ever bringing unneeded attention to their friendship which is only a very small aspect in the overall story. O'Connell always though acts as a brighter warmer side of this film without naturally without disrupting the tone of the rest of the film just through his natural charm.
Besides his chemistry with Stewart and his overall charm the only other pivotal part of his performance is his alcoholism and feelings of inadequacy. His struggle with these are especially short moments, and handled mostly only by small reactions, since as I said earlier O'Connell's Parnell is never really in the spotlight. O'Connell though despite the shortness of these moments, does convey both the fear, and eventual strength that lies in Parnell in a few short moments. This really is not a great performance, but it does act as a good supporting part to Stewart's great leading performance.