In Crouch v. Commonwealth, 26 Va. App. 214, 494 S.E.2d 144 (1997), the Court upheld the constitutionality of a checkpoint where it was established in response to an assignment given to a state trooper to conduct a traffic checking detail at a specific location in Fauquier County some time during the work week. The trooper selected the day and time, and the trooper received "verbal permission" to proceed. The Commonwealth argues that the officer's limited authority to determine the specific time of the roadblock during the designated work week does not constitute unbridled discretion. The need to evaluate weather conditions and determine the availability of other officers provides a reasonable basis for this procedure. The officer complied with the restrictions, which limited any potential abuse. His supervisor determined the site of the roadblock in advance. Id. at 219-20, 494 S.E.2d at 146-47. "The validity of a checkpoint depends upon the amount of discretion remaining with the field officers operating the roadblock. Clearly, roadblocks are constitutional when conducted according to explicitly neutral plans which completely eliminate the discretion of the operating officers." Crouch, 26 Va. App. at 218, 494 S.E.2d at 146.