The inspection rate implication of TriMet’s low fees.

By lowering the penalty for fare evasion, TriMet has chosen to raise the cost of deterring the public from stealing rides on light rail. To convince a first-time offender to pay, the frequency of inspections must now be increased.

As I’ve pointed out before, the condition for deterrence is the point at which the expected cost of fare evasion to the perpetrator exceeds the price of a ticket:

(Probability of getting caught) x (the cost of the penalty) > (price of fare)

Before these changes, TriMet needed to inspect 1% of trips to deter the average fare evader. Let’s apply this formula to TriMet’s new leniency to see how that has changed. The probability of getting caught is the rate of inspection. The cost of the penalty for the first offense is now just $75. The average fare on TriMet remains just $1.50:

(Rate of inspection) x $75 > $1.50

So the needed rate of inspection is $1.50/$75. This means 2% of MAX and streetcar trips need to be randomly inspected, which probably nearly doubles inspection costs.

As I pointed out last week, most fare evaders actually face a penalty of just $35.14. I should also point out that only children, the elderly, and the certified disabled pay less than $2.50. So a twenty-something young man that lives near a light rail stop and is studying at Portland State University has a lot of incentive to skip paying for his commute given his numbers:

(Rate of inspection) x $35.14 > $2.50

He needs a rate of $2.50/$35.14 to be deterred. That’s 7%!

Eric Shierman lives in Salem and is the author of A Brief History of Political Cultural Change.