Officer credibility is often key to winning a DUI case. Sometimes officers lie but most of the time it is mistakes and the inability to remember exactly what happened that helps win the day for the good guys.
This response is not intended to create an attorney-client relationship. The information offered in this response is for general informational purposes and is not a legal consultation. You must talk with an attorney of your choice before making any decision about your actual legal rights.
One way to discredit an officer in a DUI case is called a "Pitchess" motion. In my practice, the judge will often grant the motion (if properly written) and review the arresting officer's confidential file in chambers with the attorney for the police department and their custodial of records. However, it is rare to get a "hit" for the information you are looking for.
Another way to discredit an officer in a DUI case is to do a PC 1538.5 motion challenging the probable cause for the arrest. These motions are rarely granted, in my experience. A good criminal defense attorney will make all reasonable attempts (based upon the evidence) to get you the best result possible. Contact a local attorney in your area to represent you.
If an officer does not perform the DUI stop and arrest according to local procedures, then they can be discredited in court. They are people and people do make mistakes. Therefore, Officers make mistakes. In my experience, I find officers in my home state of Kentucky do make mistakes and I have had cases dismissed on Constitutional and statutory grounds because of those mistakes. Returning to your question, I am not aware of any system or informational source which tracks officer's mistakes.
Officers do make errors but in DUI cases they in my experience often have enough to get a conviction. You need to hire a DUI lawyer to fully evaluate your case. Good luck.
Kevin Sullivan
415-441-1052