Are there any simple and easy methods to try to detract from a police officer's credibility? I'm interested in the US legal system.
Example
When challenging a traffic ticket, you can take notes or an official report of the weather to court. Then you can examine the citing officer in front of the judge to see whether he remembers the weather. If you can get him to answer inaccurately, then you have cast doubt on his ability to remember the other facts relevant to the traffic charge.
Keep it simple
In traffic court (infraction of the law) you only have to be found 2 percent more accurate than the officer (who the judge thinks is 51 percent credible). Are there other simple ideas for achieving this?