Also in June, auto dealers filed suit challenging House Bill 2433. The measure removes the sales-tax exemption on vehicles, thus imposing a 1.25 percent sales tax on top of the existing 3.25 percent excise tax.

The law is expected to generate slightly more than $123 million for the fiscal year 2018 budget. It did not receive a super majority and secured final approval on May 26, the last day of the session.

Also in June, Republican gubernatorial candidate Gary Richardson, a Tulsa attorney, filed a legal challenge against three bills, including the new sales tax on cars.

He also challenged House Bill 1449, which puts a $100 fee on electric-drive motor vehicle registration and a $30 fee on hybrid-drive motor vehicle registrations. The law is expected to generate slightly more than $1 million.

Richardson alleges the measure was passed in the last five days of session and did not secure a super majority required for a tax increase.

He is also challenging House Bill 2348, which uncouples Oklahoma’s annual tax deduction from the federal deduction level. It is expected to raise $4.4 million. He alleges it is a tax increase that did not receive a super majority.