Defenses relating to exculpatory lost video evidence.
In some DUI-DWI arrests, the arresting officer will have a videotape recording of all or part of the roadside conversation, field evaluations and chronology of the arrest process.
If any law enforcement officer had a working camera at the arrest location, his or her department likely had in place a departmental policy that the entire arrest be recorded to be used later at trial. In the event a videotape recording was made at the scene, yet none can be located later, your attorney may use the loss of this potentially exculpatory evidence as a defense in your case.
Of course, as with any defense, there are no guarantees of victory. Your attorney must still demonstrate that the tape would have been favorable to you, or that it may have proven your innocence.