The state of Virginia is raising the financial threshold for defining a theft as a felony for the first time in almost four decades. Virginia’s experience highlights a peculiarity of American criminal law that results in petty criminals in many states being charged and punished as if they were big-time criminals.

For property crimes such as theft or vandalism, states set financial thresholds that are intended to differentiate low-level crimes chargeable as misdemeanors from more serious offenses chargeable as felonies. In Virginia, the legislature in 1980 defined theft as a felony if the property stolen was worth more than $200. Because of inflation, more and more petty thefts that were originally defined as misdemeanors became felonies with each subsequent year. In 2017, someone who shoplifted a $240 pair of eyeglasses that would have cost only $80 in 1980 would be charged as a felon — even though that was not the law’s original intent. A felony charge can result in a petty criminal receiving a prison term, being barred from many occupations and in some states losing the right to vote.

Virginia is raising its felony standard to $500. Other states have implemented parallel updates to financial thresholds for defining felony crime in recent years. But the process is inconsistent across and within states, resulting in many people being over-punished for minor crimes. This is not surprising to people familiar with the traditions of criminal law.

In the pre-computer era, when newspapers used Linotype metal typesetters, editors sometimes had a little blank space between the end of a story and the bottom of the page, and they would occasionally plug in a short item about some old law. For example, as HuffPost reports, it is illegal in Minnesota to cross state lines with a duck on your head. Such trivia was intended to amuse, but it also illustrates the reality that criminal statutes tend to stick around in their original forms rather than being regularly scrutinized for relevance.

There is an alternative to expecting legislators to consistently comb through the work of previous office-holders for criminal laws whose intent is being undermined by inflation. In many other areas of law, most notably taxation, legislators index financial thresholds such that they automatically rise in pace with inflation over time. As part of a major criminal justice reform package, the Alaska legislature has implemented this approach for the definition of theft. The law sets the threshold at $1,000 for now but mandates that the threshold will change every five years to match inflation.

Adam Gelb, who directs the public safety performance project at the Pew Charitable Trusts and advised the Alaska legislature, said that the move “is probably the first time a state has used indexing to regularly update thresholds for defining the seriousness of a crime.” If other states have the wisdom to follow Alaska’s example, resources will be better focused on serious criminals, and petty criminals will not endure the injustice of being punished as major-league offenders.