The problem is that there are no "facts" to discuss. There is nothing concrete to go on other than a photo of herself with some bruises.
There are no medical reports, no police reports, no corroborating witnesses stepping forward, and no court actions like restraining orders or even an application for a restraining order. There isn't even any evidence that the photo itself was taken any time recently, wasn't just self-applied make up, or a really good photoshop job.
It's purely he said/she said at this point. He said/she said conducted through Instagram and Twitter.
IF there was actual abuse, without the presentation of a secret stash of evidence there is virtually no chance that this will go any further.
If there was no abuse, then what's happened is that Browne's wife has stained his reputation, potentially for the rest of his life.
And yes, it is not unusual for people involved in divorces to do very nasty things to each other, especially if there is money, children, or infidelity involved. People don't always divorce on "nice" terms. Divorces are often highly charged, emotional affairs where years of disagreements and disputes can drive participants to do angry and hateful things. Spouses who once loved each other will do things with the sole intention of injuring the other, sometimes without consideration of the impact on friends, family and their children.
As for my personal point of view, I think it's more likely that the accusations are false than them being real. It doesn't mean that there's a zero percent chance, just that there are a LOT of red flags.
-didn't seek medical help from a hospital or doctor
-didn't file a police report or seek a police investigation
-didn't seek a filing for a restraining order to protect her own safety
-didn't seek an injunction to bar him from interacting with children
-didn't seek interviews with major media that would put her "on record"
-said that she didn't want to "damage" his career, but now that the investigation is complete now she wants to go to the police. Criminal charges at this point would severely damage his career.
-no additional witnesses stepping forward to corroborate a history of abuse
-no published records of 911 call logs, police logs, neighbor calls to the authorities, etc
-Browne's previous wife saying that he never abused her and that she didn't believe Browne was capable of such behavior
In the absence of evidence, reports, filings, patterns of previous behavior, corroborative witnesses, and previous family history it's hard for me to reach any conclusion except that Browne's claims of innocence seem a LOT more credible than her accusations of his guilt.