That some states enforce specific commercial vehicle regulations more aggressively than other states is no secret. Some states are known for citing truckers for light and lamp violations, others for seat belts and others for hours of service violations. And there is CSA data to prove it.

But there are also differences in how counties and municipalities within states carry out commercial vehicle enforcement, according to a report from Vigillo, Portland, Ore.

“There has to be something behind the disparities,” said Steven Bryan, Vigillo CEO during a webinar highlighting the report’s findings on Tuesday. He said the differences indicate inconsistent enforcement focus within states and differing philosophies among states when what drivers and trucking companies are looking for is balance and consistency.

Vigillo analyzed CSA enforcement data from 2012 by state, county and other categories to pinpoint enforcement trends and patterns. When looking at county-level data, it was no surprise that counties along interstate highways and other major traffic lanes reported more enforcement activity that other counties within a state, but the level of enforcement could vary widely between counties on the same interstate highway corridor, according to the report. Bryan cited Oregon and its reputation for reporting hours-of-service violations as an example.

The analysis found substantial variation among Oregon counties along the I-5 corridor in HOS enforcement. California, on the other hand, had a relatively balanced level of enforcement among the counties on the I-5 corridor. The report shows similar enforcement consistency along a 3-state stretch of the I-75 corridor in the Southeast.

The first instance illustrates that California’s enforcement focus is consistent between counties, while the I-75 example shows consistency among states. “That shows it (a consistent and balanced enforcement effort) can be done,” Bryan said.

The Vigillo report further refines the data by looking at commercial vehicle miles travelled in each state. Normalized in this way, Bryan said the data offers a more apples to apples comparison between states. For instance, to determine which state has the most aggressive commercial vehicle inspection program look at inspections per million commercial vehicle miles travelled instead of the total number of commercial vehicle inspections per state.

According to Bryan, when viewed through the million CVMT lens, states that at first glance appear to be light on enforcement are actually the opposite or states considered the most severe on inspections rank relatively high in the number of “clean” inspections per million CVMT.

The report is available for purchase at www.vigillo.com.