LOUISVILLE, Ky. (WDRB) – A bill has been filed that would clear up confusion for a stiffer drunken driving law that was passed by the General Assembly last year.

The DUI law, which took effect in April, weighs previous drunk-driving offenses from up to a decade.

This means that someone charged with four DUI’s in 10 years can be charged with a felony, punishable by up to five years in prison. The state's "look-back" period had been only five years until the law changed.

However, while some judges deemed the new law retroactive, allowing prosecutors to reach back 10 years, other judges in Kentucky have not. They and some defense attorneys say using a decade's worth of offenses runs counter to what defendants were told in plea bargains for past convictions.

The result has been unequal treatment for the same law depending on the judge who hears a DUI case.

The confusion stems partly from the language in -- or, in this case, omitted from  -- Senate Bill 56. Specifically, the bill that passed last year does not spell out whether prosecutors can use it retroactively or not. So judges have been interpreting it differently.

House Bill 251, filed Feb. 7 by Rep. Robert Benvenuti III R-Fayette, clarifies that the law should be retroactive.

Jefferson District Court Judge Sean Delahanty ruled last year that the law was not retroactive as people who pleaded guilty to DUIs in past years entered into an agreement that stipulated that only five years' worth of offenses would be considered  "and to hold otherwise would alter the agreement."

"Thousands of guilty pleas would be subject to set aside," if prosecutors tried to go back 10 years to enhance current DUI penalties, Delahanty wrote in his ruling.

"It's sort of poorly thought out," Delahanty said of the law in a July 7 hearing. "The statute is flawed. And fatally flawed."

Other judges, however, ruled the opposite. 

One of the sponsors of the 2016 bill, Sen. Dennis Parrett, D-Elizabethtown, said in an interview last year with WDRB that legislators had intended the law to be retroactive, even if it didn't specify it. If the courts didn’t work the issue out, Parrett said legislators could amend the law to specifically say it is retroactive.

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