What should be kept below an officer's knees to increase the effectiveness of a wrist lock?

To increase the effectiveness of a wrist lock, having the shoulders positioned below the officer's knees is crucial because this positioning allows for greater leverage and control during the maneuver. When the shoulders are lower than the knees, it aids in creating a more advantageous angle that can exploit the biomechanics of the wrist joint. This positioning makes it difficult for the subject being restrained to counter the wrist lock effectively, as their ability to resist or escape the hold becomes limited.

In contrast, if the shoulders are aligned with or above the knees, it may compromise the effectiveness of the wrist lock, as the body may not be in an optimal position to apply the necessary force. Therefore, maintaining this specific body alignment is essential for a successful and controlled application of a wrist lock during a physical confrontation or arrest scenario.