Concern about so-called “scanner error” at retail check-out seems to have declined dramatically in recent years after large amount of news coverage in the 1990s. Still, a recent test in the Seattle area, and fines charged to Office Depot in California and other retailers in North Carolina late last year show the issue hasn’t totally gone away.

In December, state inspectors in the Seattle did tests at 57 retailers, taking approximately 100 items through checkout and comparing the “scanner price” to the price charged by the point of sale system. If more than 2% prices checked were overcharges, the store was deemed to have failed the test. This year, 3 of the 57 stores failed. Outside of Seattle itself it was worse, as 18 of 88 stores tested, or about 20%, exceed the 2% overcharge threshold.

The good news for consumers: in 60% of the total number of price discrepancies the inspectors found, the price charged at checkout was actually lower than the price on the shelf.

Of course, “scanner error” is a misnomer, connoting that it is some problem with the bar code or scanning process that leads to the price error, sometimes causing the general consumer to mistrust the automatic identification technology being used. In reality, such price discrepancies are caused by either a failure to update the price database for an item that is retrieved by the scan, or a failure to synchronize the price marked on the shelf with the correct price in the database.

As the Seattle test shows, retailers still have significant issue with the database changes and floor level synchronization. Electronic shelf labels, a technology which would allow the shelf price to be synched with the database electronically, has never really taken off, due primarily to high costs.

The price for problems in this area can be high. In September, Office Depot in California agreed to pay a $2.3 million fine and offer consumers in certain areas of the state a $5.00 coupon to settle a lawsuit claiming that customers statewide were overcharged because of faulty readings on scanners at the checkout line. Also in September, six individual retail stores, ranging from local outlets to Wal-Mart and Staples stores, were assessed fines that ranged from about $2000 to $5000, after inspectors in the Raleigh area found numerous price inaccuracies.

For example, at one Super Kmart the test found an error rate of 5 percent based on 15 overcharges out of 300 items.

The stakes can be high – in North Carolina, each store could have been assessed a civil penalty of up to $5,000 for each violation under the Weights and Measures Act of 1975, which would have resulted in fines of tens of thousands of dollars.