
Quoting
L-1
Don't do it in person. Write a letter to the issuing agency. Mark the front of the envelope ATTN CUSTODIAN OF RECORDS.
Inside attach a copy of your citation, state you are seeking informal discovery in connection with that citation. Don't discuss whether you have a court date, simply state you are seeking informal discovery. At a minimum ask for the following:
1. A copy of the officer’s copy of the citation, including the back side containing any notes he may have made in connection with this enforcement contact.
2. A copy of all other reports, notes and other paperwork made in connection with this enforcement contact.
3. A copy of the calibration records for all speed measuring devices used in connection with this enforcement contact.
4. A copy of all relevant speed surveys related to this enforcement contact.
5. A copy of the patrol vehicle recording made in connection with this enforcement contact.
6. A copy of all personal recordings the officer may have made in connection with this enforcement contact.
Once you have those you will know what you are up against and whether there is anything to base a defense on.
As a side note, most patrol vehicle recording devices do not activate until the emergency lights come on. This means the violation probably was not captured and retained on camera unless you engaged in a prolonged pursuit with the officer. What it should capture is your interaction with the officer during the traffic stop. You need to review this part very carefully as drivers have a tendency to admit the violation and apologize for their driving, which is captured on the video. When that person goes into court and denies any wrong doing, the video is played in which they admitted the violation, destroying their credibility. If the video shows they were rude, argumentative and abusive to the officer, any sympathy they may have had with the judge can go out the window.