It's easy enough to get on the new Green Line light-rail train. You just hop aboard.

There are no turnstiles to go through, no conductors to check your ticket. Passengers must pay a fare, of course. Machines validate Go To cards and another proffers passes for cash or credit. But no one is actually there to ensure folks aren't riding for free.

Or are they?

While checking police incident reports this week, I noticed several fare enforcement reports were filed regarding nonpaying passengers on the Twin Cities' shiny new train system that runs mostly along University Avenue between St. Paul and Minneapolis. Several times, officers approached passengers and asked for proof of a valid fare.

Several times, the passengers couldn't show it.

Which prompted me to ask the question: Since our light-rail system is sort of based on an honor system, how often are passengers actually honoring their fare?

According to Metro Transit spokesman John Siqveland, Metro Transit police check tens of thousands of fares per week and issue citations to about 2,000 fare-evaders per year on the Blue Line. He expects the same numbers to be the norm on the Green Line.

"The practice of fare enforcement is not exceptional, but how we police our rail lines," he said.

By the way, skipping out on paying for a $2.25 fare could cost you much more than the fare itself. While first offenders generally get a warning — and an escort off the train — the penalty for not paying is misdemeanor ticket and a $180 fine. Offenders also can be banned from the entire transit system for a month — all for failing to pay a fare.

So, just how common is the problem? Surprisingly rare. Siqveland said that Metro Transit police fare checks over 10 years on the Blue Line show a rate of fare honesty of 99.2 percent.

Considering that riders hopped aboard the Green Line more than 27,000 times a day during its first week and there were only a handful of citations, it appears the Green Line is off to a decent start.