A checker in civilian clothes enters one door of the car and checks tickets. Anyone not already checked, who gets up to leave by the other door beforehand is then stopped by his/her partner for the ticket check.

Frequently, there would be these fare ambassadors who would enter the train at one stop or another and go around and check everyone's ticket status. It was fairly unobtrusive, and I thought it was a good way to detect the freeloaders. I don't ride the light rail, but I don't see a problem with this approach.

There usually was a guy who'd go through counting the number of passengers. If the count didn't match up with the number of tickets sold, they'd then ask to see tickets or your ORCA card.