WALTER: Tell him if he'll reprieve Earl Williams, we'll support him for senator. Tell him the Morning Post will be behind him hook, line, and sinker.
Walter is offering to sell the paper's endorsement to the governor for political backing. That's bribery; the same crime that Walter nails the Mayor for at the end of the film. Why is Walter better than the Mayor? (Probably because he's played by Cary Grant.)
WALTER: It was a coloured policeman. You know what that means.
Walter is arguing that black voters will demand that Williams be executed. But the point he's making is also that black policeman, and black voters, encourage corruption and injustice. Black people faced tons of discrimination and prejudice in the 1940s. And His Girl Friday not only reflected the attitudes of its time, but also contributed to them.
HILDY: Look Walter, you get the interview with Earl Williams. Print Egelhoffer's statement. And right alongside of it—you know, double column—run your interview. Alienist says he's sane. Interview shows he's goofy.
WALTER: Aw Hildy, you can do it. You could save that poor devil's life.
Walter appeals to Hildy's instincts for justice… maybe. Actually, the appeal mostly works on Bruce. Hildy is only swayed when Walter offers money. (She and Walter are quite a bit alike.)
ROY BENSINGER: A new lead on the hanging—This alienist from New York, Dr. Max J. Egelhoffer, Egelhoffer, yeah, he's gonna interview with him in about half an hour in the Sheriff's office... Here's the situation on the eve of the hanging... A double guard is being thrown around the jail, the Municipal Buildings, railroad terminals, and elevated stations to prepare for the expected general uprising of radicals at the hour of execution.
MURPHY: The Sheriff has just put two hundred more relatives on the payroll to protect the city from the Red Army which is leaving Moscow in a couple of minutes.
The Sheriff is completely corrupt and ridiculous—and the newspapermen are the ones who know it. They expose injustice… though they're also often jerks, and printed lies about Mollie. It's not really clear whether they're crusading for justice, or just trying to print an enjoyably scandalous story.
WALTER: No, no, never mind the Chinese earthquake for heaven's sake... Look, I don't care if there's a million dead... No, no, junk the Polish Corridor... Take all those Miss America pictures off Page Six... Take Hitler and stick him on the funny page... No, no, leave the rooster story alone—that's human interest.
Walter rearranges the paper for the big scoop about the government scandal and Earl Williams. The paper will report on the triumph of justice… along with the rooster story. Can't get rid of the rooster story.