It is asking for a cop to be against you from the start.  Since he can't see
in, he immediately assumes the worse as he approaches, so you can usually
kiss any leniency in a ticket goodbye.

The best thing to do when pulled over in the day is roll both sides down and
at night, roll them down and turn on the dome or interior lights.

I was driving a coworker's truck helping him move at night once and his
truck was from Florida with the dark tint.  It was dangerous at many
intersections.  I had to roll the windows down to see, and it was winter.  I
also had a van once that the rear windows were dark tint and you couldn't
see anything for backing up at night.  I peeled it off within the first week
of owning it.  For privacy, there are always curtains.