A jury convicted Kwame James of driving under the influence of alcohol to the extent he was a less safe driver and of making an improper lane change. James had earlier pled guilty to the offense of speeding. He appeals, contending the trial court erred in granting the State’s motion to exclude certain evidence about the arresting officer’s training and certification, and erred in restricting the testimony of his expert witness regarding field sobriety tests. For the reasons that follow, we reverse. 1. At the hearing on the State’s motion in limine, the State argued that it was offering the police officer “strictly as a POST certified law enforcement officer. We will not be offering him as a NHTSA National Highway Traffic Safety Administration certified officer.” The State therefore asked the trial court to prohibit the defense “from doing any sort of cross examination into the NHTSA training that this officer may or may not have, or into the requirements that NHTSA has set forth for the administration of field sobriety evaluations.” The State responded affirmatively when the trial court asked if it were going to present the police officer “as a lay person with training through the academy,” and was not going to present him as an expert witness. Relying on Cantwell v. State , 230 Ga. App. 892 497 SE2d 609 1998, the trial court granted the State’s motion, ruling that the State could put up the officer “as POST Peace Officer Standards and Training certified training through the academy and that —of what he learned at the academy insofar as the leg lift, the HGN, the walk and turn. This will not include the clues and other matters that are covered by nystagmus.”
“The right of a thorough and sifting cross-examination shall belong to every party as to the witnesses called against him.” OCGA § 24-9-64. The right of cross examination is a substantial right, the preservation of which is essential to the proper administration of justice and extends to all matters within the knowledge of the witness, the disclosure of which is material to the controversy. This right should not be abridged. Fair v. State , 140 Ga. App. 281, 282 1 231 SE2d 1 1976. “It is the duty of the court both to protect a witness under cross-examination from being unfairly dealt with, and to allow a searching and skillful test of his intelligence, memory, accuracy and veracity. As a general rule, it is better that cross-examination should be too free than too much restricted.” Harris v. Central Railroad , 78 Ga. 525, 534 3 SE 355 1887. “The right of cross-examination in this state includes questioning a witness about subjects relevant to any of the issues in the case, not simply those matters elicited on direct examination.” Stone v. State , 250 Ga. 718, 719 300 SE2d 500 1983. We review a trial court’s ruling that curtails a cross-examination for abuse of discretion. Stevens v. State , 213 Ga. App. 293, 294 2 444 SE2d 840 1994.
