Since DC is going for the really-real world in this reboot, I'm going to assume that the wife beater recovered and either continues to assault his wife in one form or another or he killed her as it too often happens here.
The really real world? Come now. The main character is a man who can run faster than a speeding bullet, who gets hit in full on by a gigantic future-train going at full speed without dying. In fact, I doubt if he'll actually need any serious medical attention. And he does it all while wearing a red cape that used to be his baby blanket.
We are dealing with
Superman. Realism went out the window the moment Siegel and Shuster decided he was based on guys like Samson and Hercules. If it was realistic at all, you would be reading about someone else. Besides, what would you have Superman do about the wife-beater? Just let him keep hitting her? The precedent here is for them to get thrown through a wall.
Then, what was the point in attacking him? If they had hard evidence, they should go ahead and either publish it or turn it over to the authorities. The forced confession and the methods Clark used to get it are only going to make the criminal look like a victim once the story is spun.
Because Glenmorgan was in charge of the city, like Luthor in the 90s. Evidence or no evidence, they weren't going to arrest him. They probably wouldn't even have published the story, he probably owns the paper or something. But if he were to turn himself in? I admit, the Superman angle does make him look a bit like a victim, but now the evidence that they have against him will be at least visible, instead of dismissed because of who it's against.
Superman doesn't act like judge, jury, and executioner and toss people out a window and they end up sustaining two broken hips and a number of broken or fractured ribs. Superman certainly isn't stupid enough to give a well-connected criminal ample ammunition by scaring a confession out of him and possibly dilute any hard evidence he may have.
First: I pointed out that Superman doesn't kill anyone in the story. He injured one guy, off panel. To be honest, I'm not sure how I feel about that either, but I'd imagine Superman decided to keep an eye on that woman so he can stop her husband if it happens again. Second: Ammunition to what? Take Superman down? He's not exactly going to respond to a court summons. Don't worry though, if you're so eager to see that Superman gets captured, just look at the end of the story. Luthor helps General Lane take him down, probably killing quite a few people in the process, and we're left with a teaser for "Next Issue: Superman in Chains!". There's your pro-establishment "hero", if you want him. Hail Luthor.
You gotta wonder what this new "socially-conscious" Superman would do if he came upon a policeman giving a known-criminal some stick time: Does he stop the policeman and help the scum bag or does he join in on the beat down?
What kind of question is that? You might as well ask it of the "Classic" Superman, I don't think the answer would be that different. If the guy's actually a scumbag, Superman sticks around to make sure he's properly arrested and not just smacked up. If he's a good man forced into doing non-evil but extravagant illegal things by societal pressure, Superman probably not only stops the cop, but gets the guy back on his feet so he doesn't have to keep turning to crime. Remember: Champion of the Oppressed. It depends on whether the guy is a murderer or a thief or whatever too, but anyone beating up a guy, even a cop beating up a crook, isn't something Superman will just ignore. ANY Superman.
Do you remember Chuck Austen's run on Action Comics a few years back? Austen went for the Golden Age characterization, had Superman smile, clearly enjoy his calling/job/whatever complete with puns, and even had him kneecap some villains with his heat vision. The end result? A disaster. A number of retailers boycotted the run, Austen was fired (hasn't done much in comics since), and the run was completed by an unknown writer under a pseudo-name.
Austen went overboard. I do think that the high sales and mixed-but-mostly-positive reviews on Action show that people are willing to accept a pro-active, enjoys his job Superman. Austen's was more like a psychopath. Morrison's Superman doesn't kneecap anyone with his heat vision. He takes down a businessman nobody else would try to. He tries to stop a train with a bomb on the tracks. He stops Luthor from destroying a building with people still in it. And he throws ONE dirtball through a window off panel. Horrible bully and idiot, or relatively heroic Champion of the Oppressed?
Frankly, I don't even know why I have to ask.