Note: Although some of the information below will be relevant nationwide, the specific legal rules cited are California law. All of our cases representing victim's thus far have been at the Larson Justice Center in Indio, California, Riverside County.
The short answer is no, only the prosecution can charge people or dismiss cases. Once the police get involved, the situation is out of your control.
That said, it frequently happens that in the heat of the moment people call police and give statements that they later regret, usually because they either lied or greatly exaggerated the incident. When the "victim" later decides to tell the truth, they are often threatened with prosecution for filing a false police report or flatly advised that they are a "liar". Interestingly, they are only a "liar" if they say that nothing happened, but are never a liar when they say something that the prosecution believes will lead to a conviction. Therefore, I write this information to those who are in the position where they fabricated or exaggerated to police.
As the "victim" in the case (and usually the only eye witness to the events), there is much you can do to later derail the prosecution of your loved one, if you are determined, because you initially misled the police and the prosecutor doesn't believe the truth. Domestic violence prosecutors, especially here in Riverside County and the Coachella Valley, are often paternalistic crusaders who think they know what is best for your family better than you do. They will seek out long prison terms with cold disregard for the consequences to your family.
1) Do I have to testify?
There is no simple answer here. But the process goes something like this:
The first stage the prosecution takes to bring you to court to testify is usually mail service - meaning that they will mail you a document asking to call them to confirm that you got the document and are coming to court. Don't call the prosecution. This will let them know that they have a valid address and responding will technically compel you to go to court.
The next thing the prosecution will do is send an investigator or cop to try and find you and personally serve you the paperwork saying you need to go to court. Personal service can be avoided - don't answer your door, if you live in an apartment, consider moving. If a strange person asks your name, refuse to answer.
If you have been properly served, you must go to court. The judge will order you to answer questions that the prosecutor is asking. However, if you refuse to testify, California CCP 1219 protects you - you cannot be jailed for refusing to testify. The judge may order you to consult with domestic violence counsellor, but it is unclear what the judge can do if you refuse. There may also be some fines.
Note that if you take this route and refuse to testify, the judge and prosecutor will probably be very angry with you. This is because they want to put your partner in jail and tear apart your family - and they demand your cooperation. The anger is all bluster, with little consequence behind it. Stand your ground.
2) I haven't been subpoenaed, but I want to go in and testify to just set the record straight. Will the judge drop the case if I do that?
No, and this is the worst idea possible. You are the only witness and the judge and prosecutor won't believe you if you say nothing happened. They will use your first statement to police to contradict your second, and only believe the one that aids in conviction.
If you never testify, the prosecution will likely have NO evidence in your partner's case and will have to drop the charges. However, if you do testify, the prosecution will be able to have police testify to your other statements you made in the past, allowing the prosecution to proceed.
This is due to a quirk of our constitutional protections for defendants. The defendant's attorney has a right to confront any witness in open court. If the defense is not afforded the right to cross-examine a witness, none of the statements of that witness can be used as evidence (at least those statements made to police when formally investigating the case).
In short, once you open your mouth as a witness, the prosecution can put on police officers to testify about your prior statements and can play audio and video recordings of those statements.
3) How should I deal with the prosecutor?
You can start nice and go nasty later, but it is harder to start nasty and go nice. You should nicely explain your position to the prosecutor on the case - it may result in a good deal for your partner. If the prosecution treats you like a child or ignores you, it probably won't hurt to get mean. If the prosecutor hates you they may want to dump the case to avoid contact with you. A colleague had a case where the prosecutor hated the "victim" so much that the prosecutor said "I want to give the defendant a stick to beat her with" - the case later settled very favorably.
One thing you should not do in dealing with the prosecutor is discuss the facts of your case or start weaving out new story lines. This will not make anything better. Keep focused on the fact that your partner is being treated unjustly and explain to the prosecutor that the case is hurting you and your family.
4) Effective Recantation
Usually it just looks bad when domestic violence witnesses testify and give a totally different story. The defense attorney often will argue that the person is just a liar and you can't believe anything he/she says (this can be very effective). Technically the prosecution can charge you with filing a false police report if you lied to the cops, or perjury if you lie while testifying, but in practice I have never seen this happen (but I'm sure it must from time to time).
Often a better tactic is to produce evidence of mental illness or witnesses to testify that you are untruthful. For example, I had a case where the alleged victim's mother and father were both testifying for the defense that she was a liar and often injures herself when she drinks (the case was dismissed). Give the defense a list of people that could testify that you are a liar.
Your appearance at the court hearings may also influence the proceeding. Dress like a crazy, trampy liar and you may help influence the case to your partner's benefit. For example, I once observed a recanting witness come to testify carrying a coffin backpack with chains as straps - she set the little coffin on the witness stand so the jury could see it throughout her testimony. Consider tiny shorts, a tank top, t-shirts advocating drug use, dirty clothing, messy hair, or even shaving your head! For male "victims", get a tattoo across the back of your shaved head that says, "I rule bitches!" or something similarly demeaning to women. Be creative! But also be yourself - I mean, there must be a little crazy in you if you got this ball rolling....
5) Consult with an Attorney
Unlike a person charged with a crime, an alleged victim has no right to a court appointed attorney. I am happy to meet with victims at no charge for a initial consultation. I can provide some good tips for you specific to your case, but if you really want to be effective and show the prosecutor how seriously opposed you are to the prosecution, then hiring an attorney is your best option.
Call Law Office of Forest Wilkerson at 760-777-4322.