What Happens in a DUI Trial?
Once the prosecution has rested, including the introduction of any exhibits that are referenced during this phase of the trial, the defense will make a motion for a dismissal on the basis that there is insufficient evidence to allow the case to get to the jury, that no reasonable jury could convict the defendant based upon the evidence offered by the prosecutor. These motions are routinely denied, but granted often enough that the competent DUI lawyer should not be deterred from making them in every case.
Now the DUI defendant has an opportunity to call witnesses to offer testimony to support his or her case. This may be in the form of civilian witnesses who were with the defendant and can testify to his or her lack of impairment from alcohol; it may be a "no driving" defense, where the real driver comes forward and admits to having been behind the wheel; it may be a defense expert, who will scrutinize the field sobriety tests, chemical tests and offer an opinion that the defendant was under the legal limit and not impaired at the time of driving.
During the defense case, the DUI defense lawyer is not allowed to ask leading questions of defense witnesses. Instead, it is the prosecutor's opportunity to ask leading questions of the defense witnesses while they are on cross-examination. The drunk driving defense lawyer breaches his duty to his client by not preparing his or her witnesses to undergo this cross-examination. This is where a significant amount of trial experience comes in handy; it is the lawyer's job not to allow the witnesses to appear to be dishonest.