By: Perry J Zucker – February 2, 2013
Definitions of Probable Cause
“`A well-grounded suspicion that a crime has been or is being committed’”. The facts and circumstances must show a “`reasonable ground for belief of guilt.”(+)
Most “Probable Cause” traffic stops are for an indirect reason(s). Some of these vehicle traffic stops were initialized by:
Laser / Lidar Speed Guns measures speed by utilizes an infrared light beam, which is activated by the Police Officer, at a moving target (your vehicle). The officer observed the target vehicle (yours / defendant) and reads the speed display of the laser/ lidar unit.
Radar Gun / Unit speed measures speed by utilizes RF, which is activated by the police officer, at a moving target (your vehicle). The officer observed the target vehicle (yours / defendant) and reads the speed display of the radar unit.
Pacing / Pace measures speed of the target vehicle (yours) by keeping a uniform distance from the rear / front / side for a specific distance(s) and reads the speed of his/her speedometer.
Gap Time / Timing / Vascar measures speed of the target vehicle (yours), utilize a method that uses a timing theory between two (2) points with a known distance.
Disobey Traffic Control Device – The police officer observes a target vehicle passes a traffic signal, sign, and/or crossing a pavement marking(s), etc.
Faulty Equipment – The police officer observes a target vehicle that has standard equipment not operating, e.g. head light(s), tail lights, etc. and/or equipment that should not be operating.
Once, the vehicle (yours) is safely pulled over, the police officer / trooper will make a determination, if any further action(s) should be taken, such as authorized or unauthorized search, person of interest interview(s), traffic ticket(s) and/or arrest, as well as possibly impounding the vehicle in question.
In order for a law enforcement officer to make a lawful probable cause traffic stop, he/she must meet certain key elements (See Above). It is these type of cases, that a probable cause traffic stop expert witness will be critical.