Calibration records are critical to establishing the reliability of breath testing devices. If documentation shows the device was not calibrated according to required schedules or that calibration produced out-of-spec results, this can undermine trust in the readings obtained at the time of testing. In Kosciusko cases, a detailed review of maintenance logs and calibration certificates is often the first step in determining whether a valid challenge exists. Gaps or discrepancies in those records may support a motion to exclude breath test results. Successful suppression based on calibration issues depends on the specific facts and how the court views the significance of the defect. Courts consider whether calibration failures likely affected the particular result at issue. When calibration gaps coincide with other procedural problems, such as improper observation periods or operator errors, they strengthen the argument that the machine’s reading is unreliable. Housley Law examines all related records from Attala County to build persuasive motions when justified.