When law enforcement (police) utilizes radar technology to monitor vehicular speeds from a side street at an angle, it introduces distinct challenges and considerations. The operational mechanism can be outlined as follows:

Radar Angle: Radar devices determine the speed of a vehicle by emitting radio waves and evaluating the Doppler shift in the waves that are reflected from the moving vehicle. When the radar is oriented at an angle to the vehicle's trajectory.  This arises because the radar captures only the speed component that is directed towards or away from the radar device.

2. Effect

3. Legal Considerations: In numerous jurisdictions, the precision of radar measurements is vital for law enforcement and subsequent legal processes.

4. Strategic Positioning: Police may employ angled radar placements tactically to decrease their own visibility and to monitor vehicular activities from positions that are less likely to attract scrutiny.

In conclusion, while radar devices can function effectively from an angular orientation, the precision of the speed assessment is influenced by the angle at which the radar system is deployed.