In most Ohio DUI/OVI cases, the evidence includes police officer testimony and police cruiser video. Officer testimony is sometimes not corroborated by the recording from the cruiser video. In such a situation, a judge or jury has to decide if they believe the officer or their own eyes. Such a situation arose in the recent case of State v. Jarosz, and the judges believed their eyes.
In Jarosz, the discrepancy between officer testimony and cruiser video involved the officer's use of 'pacing' to determine the defendant's speed. To measure a vehicle's speed by pacing, an officer must follow the other vehicle at the same distance for a period of time. By doing so, and by knowing the speed of the cruiser, the officer can conclude the other vehicle is going the same speed as the cruiser.
During a hearing on Mr. Jarosz's motion to suppress evidence, the officer testified about pacing the defendant's vehicle. The officer said he first did a visual estimate of the defendant's speed, without pacing, and concluded the defendant was exceeding the 45 mph speed limit. As the vehicles entered a 40 mph zone, the officer paced the defendant's vehicle and maintained the same distance for 12 seconds.
In his testimony, the officer acknowledged the importance of maintaining the same distance between the defendant's vehicle and the cruiser. He also acknowledged that going faster than the defendant would make it impossible to get a good speed measurement. The officer testified he was "a hundred percent positive that [he] had a good speed pace on him and logged a speed pace of 48 miles per hour in a 40 zone".