PROVIDENCE, R.I. (WPRI) — A federal trial began Monday morning in the ongoing fight over tolling big rig trucks on Rhode Island highways.

The American Trucking Associations (ATA) filed the lawsuit back in 2018, along with Cumberland Farms, M&M Transport Services and New England Motor Freight.

The plaintiffs argue the RhodeWorks plan that set up the tolls — which was signed by former Gov. Gina Raimondo in 2016 — is discriminatory toward out-of-state truckers. They say the tolls are unconstitutional and set a bad precedent for other states to follow.

Class 8 through 15 trucks are the only vehicles being tolled. In their opening statements, the plaintiffs said that group only makes up about 3% of all vehicles on state highways, but they’re paying 100% of the tolls.

In its defense, the state argues that RhodeWorks was fully vetted by the federal government. State officials say their research found that 70% to 80% of the damage done to highway bridges is caused by large tractor-trailer trucks frequently traveling the highways.

A majority of the trucks are from out of state, but the plaintiffs argue that out-of-state drivers end up having to pay more than intrastate drivers because there’s a cap on how much a truck pays daily when passing through the same gantries.

However, the state showed research suggesting that interstate trucks actually got more of a discount.

Since this is a bench trial, there is no jury, leaving U.S. District Judge William Smith to decide the outcome.