Originally Posted by MikeDT
Because they're cops and not catwalk models.
Most likely clip-on ties as well, in case the prisoner attacks and tries to strangle them by grabbing the ties.
Those are real knots, notice how shitty? A clip on looks perfect.
The one of the left is one of those guys that loosens it every night and tightens it again in the morning. You can tell by the way the knot has contracted over time.