For more than a year, CBS News New York Investigates has shared stories of families torn apart by alleged drug-impaired drivers begging Albany to act.

Law enforcement says a loophole in New York's law keeps some drivers from ever facing charges.

Investigative reporter Mahsa Saeidi has been with these families every step of the way and has new information on their push to close that gap.

The loophole in New York's law

Police say to charge an impaired driver, they must name the exact drug ingested, and confirm it's on a pre-existing list. If they can't, their case collapses, and alleged impaired drivers are off the hook.

New York is one of a handful of states that focuses on a list, instead of impairment. Lawmakers won't say why.

Back in March, Saeidi tracked down State Assembly Speaker Carl Heastie, who said expanding the law would give police more discretion to judge impairment.

"That's the thing. You have a Breathalyzer if someone has been drinking alcohol," Heastie said. "I'm also concerned that particularly communities of color get overpoliced."

Advocates say leadership blocked the bill last session. With lawmakers returning in January, they believe it'll pass this time -- if leadership allows a vote.

"This is a no-brainer for me" 

As for family members of victims, they say they feel compelled to come to drugged-driving conferences year after year, like one held in Manhattan on Wednesday, to share their stories again, hoping this time state leaders will close the loophole in the law.

"Dec. 5, 2014, I kissed my husband goodbye," Jawana Richardson said. "We were going to a party that night. They told me my husband had been killed on the Southern State Parkway."

"A repeat offender drugged driver crashed into my brother," Steven McDermott said. "He was a teacher. He was the perfect role model for me and and my other brothers as well."

"It don't matter what kind of alcohol is in your system. You're a DWI. Why should it matter [which] drugs? If you can't drive, you can't drive," added Tim Carpenter, whose son was killed.

"These are lives that have been taken by irresponsibility. This is a no-brainer for me," added Empress Henderson, who also lost a son to an alleged drugged driver.