As someone who has worked in the criminal justice system- albeit briefly- I can attest that “it is the man that gets arrested every single time.” is untrue. In fact most states have laws that dictate that, in a domestic dispute, responding officers must remove- but not necessarily arrest[/I— at least one participating party (spouse, significant other, child, parent, roommate, renter, etc.) from the premises. Who gets removed is situationally dependent, and officers recieve training on how to assess who should go, including asking all involved if they have a safe place to spend the rest of the evening. They can even ask for someone to voluntarily leave, at which point a volunteer will be granted time and access to the premises to recover some personal effects with police protection.
If you continue being a hothead and don’t listen to the cops, or worse, resist restraint attempts or take a swing at one, you WILL get arrested. If the responding officers are aware of a repeated pattern of behavior that results in multiple call-outs to the same address, someone WILL get arrested.
Summing up,
1) it isn’t always the man who gets hauled off;
2) being removed does not equal arrested, and may even be voluntary;
3) arrests usually only occur if someone wants to press charges or is unresponsive to the lawful orders of the officers.
The question is, how is that applied in the field? I have seen quotes from a Police Officer saying that they will arrest the man without exception even when it is the man who has been wounded.