The Police Chief of Austin, TX bicycles.  Here he instructs motorists how to pass bicyclists safely:
Austin Police Chief on safe passing of bicyclists

Video of aggressive driver passing incorrectly.  Individual cyclists are now using video to document and submit evidence on unsafe passing.  This driver was ticketed.

Austin also enforces the three foot passing law with plain clothed police riding bicycles with GoPro cams.  They issued 104 citations according to this story.

Thanks BikeWalkNC for these great education resources for police, and thanks Austin, TX for your leadership in progressive and proactive police work making the streets safer everyone.

The average American spends 40 hours/year stuck in car traffic.  Waiting for a safe moment to pass bicyclists is not a major cause of motorist delays.