More serious films should have exclamation marks--even Powell & Pressburger weren't above it. In the Mood for Love!, 12 Angry Men!, Moonlight!, Where is the Friend's house‽, etcetera.
The shots of Stamford, CT, made me feel unremembered and unexperienced nostalgia for 1947. The small towns of the era were so aesthetically pleasing. (The film claims Stamford as small, not I.)
Kazan plays this true crime story straight, and the one time it lightly tilts into theatrics, Dana Andrews apologizes. There fortunately isn't an ounce of the sensationalistic, and that's to Kazan's immense credit, especially when he's stocking Lee J. Cobb and Karl Malden in his casts. Whether you need the sensational to make a true crime procedural intriguing depends on your predisposition; the facts as they are generally suffice. Really, Andrews nobly sticking to the inherently inspiring script suffices. His real-life counterpart--probably the best Attorney General of the U.S.--did, nevermind the moneyed and fascistic interests pressuring him otherwise.