This is a pretty good article on domestic violence laws and how charges are brought forth. It looks like a lot of the laws are cited out of Colorado, but it seems to me that a lot of the laws are the same in many states.
Written by Charles E. Corry, Ph.D. A quick Google of his name brings up plenty of Domestic Violence literature...
http://www.dvmen.org/dv-6.htm#plea
Some "highlights"...
But in all domestic violence cases you are presumed guilty until you can prove your innocence and due process is nonexistent.
In prosecuting domestic violence cases the district attorneys are out to win. Whether you are guilty or innocent is of no consequence to them. They most definitely do not want to be perceived as soft on domestic violence defendants. Further, domestic violence is now being called the new Jim Crow. If you are black you are much more likely to be arrested, convicted, and spend a longer time in jail on domestic violence charges.
In many cases where an abusive female has been arrested for domestic violence she then goes to a shelter or victim's advocate and obtains a civil restraining order against him that forces him out of his own home. The shelter or advocate group will also frequently provide her legal assistance at taxpayer expense. Males, of course, have to pay for their own legal defense.
. The police will enter your home night or day without a warrant and search for evidence of violence. We have repeatedly heard reports that women cut up clothes, scratched or bruised themselves, or broken things in the house, and then blamed their male partner. Deliberate self injury is five times as common as criminal domestic violence but such false allegations and perjury are never prosecuted.
Once reported to medical authorities, the other party in the dispute will be arrested regardless of any physical evidence. The statements of the party seeking medical aid will not be questioned before the trial. Medical evidence and prior history of the accuser, e.g., alcoholism, mental instability, infidelity, prostitution, or pre-existing medical problems of the "victim" will almost certainly be suppressed by the prosecution during trial. From first to last the attitude will be: You are male, you are guilty! And if you are black you are doubly guilty. Domestic violence laws are referred to as the new Jim Crow in black communities.
No warrant for the arrest is required even if it is made days later by officers who never saw or talked to the woman making the accusation.
The District Attorney cannot dismiss a domestic violence case or plea bargain it to anything that does not involve domestic violence C.R.S. § 18-6-801 (3). Realistically, the only way you can clear your record of a domestic violence charge is to go through a jury trial. Bear in mind that the prosecutor will attempt to bluff you about going to trial, and your defense attorney may recommend a plea bargain because he gets paid but doesn't have to go to the time and effort of preparing for trial.
It goes on and on....