Louisiana Senate lawmakers unanimously approved a bill to outlaw a device that can change some traffic signals from red to green.

A traffic-light changer is designed to allow police, fire and other emergency officials to clear intersections before they approach. But some drivers have managed to purchase them on the Internet for about $325, The Times-Picayune reported.

HB188, sponsored by Rep. Cedric Richmond, D-New Orleans, was approved by the Senate 38-0 June 10. The bill, which previously passed the House 104-0, has been sent back to the chamber for approval of Senate changes.

The bill is intended to deter anyone other than public safety and transit agencies from buying, selling or using the so-called mobile infrared transmitters, or MIRTs.

Richmond’s bill stipulates that violators be jailed for up to a year, fined a maximum of $5,000, or both.

The devices, which sit on a vehicle’s dash, are not regulated by current federal standards because they rely on a beam of light instead of a radio wave to trigger the light-changing mechanisms that have been attached to some intersections.

A recent U.S. Department of Transportation survey showed the devices are in use at 26,500 intersections in 78 cities across the country.

State Police spokesman Lt. William Davis told the newspaper he is unaware of any serious problems with the devices in Louisiana but said if the devices become popular and drivers start using them “it would cause mayhem” with traffic, increasing accidents, injuries and fatalities.