State lawmakers killed a bill that proposed expanding the definition of drugs and substances in Hawaii’s impaired driving laws after they failed to reach an agreement on the measure in the waning hours of conference committee hearings Thursday.

With a 6 p.m. deadline looming, a conference committee of House and Senate legislators deferred Senate Bill 641, but indicated they may return to it next year.

“Perhaps we can work with the counties as well, and have more conversations with the police department and prosecuting attorneys to make sure we have nice, clean bills,” Sen. Lorraine Inouye, one of the conference committee co-chairs, said.

The Senate’s original draft authored by Sen. Karl Rhoads would have  expanded the definition of “drug” for purposes of DUI enforcement to include anything that “can impair the ability of a person to operate a vehicle safely.”

It would also include any plant or chemical that could impair driving. The broad definitions raised concerns with the public defenders office.

Rep. Chris Lee, the House Judiciary Committee chair, changed the measure to make it a petty misdemeanor if anyone is caught driving impaired by the substances that would be included under SB 641.

On Thursday morning, Rhoads, Inouye and other senators offered the House representatives a new draft of the bill that nixed Lee’s changes and exempted the new drugs from being counted toward habitual offense, which is considered a Class C felony.

However, lawmakers agreed to HB 703 which would ban the sale of alcohol to anyone who was charged with habitual offense. The bill also slaps heftier fines for DUIs and extends the time a persons license would be suspended.