top of page

The Length Arm of the Law

There is a concept in the law that is probably better understood by teenagers than police officers and truckers. When you were growing up, authorities in your life set rules….maybe it was your parents or a teacher. These rules were baseline regulations designed to control behavior. However, any teenager can tell you that these rules are constantly open to revision. Sometimes the rules are loosed based on reward. Other times they are restricted based on consequence. Either way, there is always a foundational place to come back to. The same philosophy is true when trying to understand the length laws in the Illinois Vehicle Code…but like all things trucks, a bit more complicated.

When it comes to understanding length, the universal misconception is the law is a “one size fits all” regulation. This could not be further from the truth. Prior to 2010, only legal height was uniform in Illinois. Weight, width, and length law each had different sets of legal maximums based on the classification of highway. After 2010, weight and width laws joined the height law in the club of statewide uniformity. This left only the length law with a tiered system…five tiers to be exact, and different length limits depending on the configuration of the vehicle. This article is not about to attempt to explain away all the nuances of length law. The ITEA has produced a resource document for its members to simplify this.

Many times truck officers will stop a truck for a length violation such as a semi-tractor trailer combination being over 55’ long on a city or county road. The immediate response from the trucker is usually “I didn’t see a sign restricting anything”. He is correct. There was not a sign restricting length because 55’ overall length is legal for that road. Had a local unit of government exercised its authority to restrict for less than legal, a sign would need to be posted. The same is also true if the authority had expanded the length dimension to that of a Class-II highway…a sign would also need to be posted. Like the teenager with a baseline rule of conduct that can be loosed or tightened, the same is true with legal length on any particular road.

While technology for atlases, maps, and GPS systems are improving, they are usually the kiss of death for truckers trying to avoid negative police attention. A teenager will have a set of rules to follow at home, but a different set of rules at school, summer camp, and his part-time job. Just because different authorities in his life intersect with one another, it does not mean that one authority trumps the next. Rules of classroom conduct may be well and good at school, but those rules may not jive with the rules of mom and dad at home. A semi-tractor trailer may have liberal maximums on a Class-I or II highway, but once it turns onto an intersecting local road, there is a different set of legal maximums to comply with. Mapping systems that show intersecting roads do not give authority for trucks to violate the maximum length laws of a contiguous road.

Whether or not the length law is fair and equitable is a philosophical matter to be played out in our political and legislative systems. In the fall of 2011, the ITEA met with leaders from the Illinois State Police, IDOT, Mid-west Truckers, the Illinois Trucking Association, and the Illinois Municipal League to begin working on revisions to the length law. There are a lot of justifiable and competing interests at stake, and it will take time. Conversations have to start somewhere…without teenagers though.

1 view0 comments

Recent Posts

See All


bottom of page