AUGUSTA — A bill to make heroin possession a felony offense advanced on Monday after lively debate about whether the threat of lengthy jail sentences motivates drug users to seek treatment.

Lawmakers have been grappling with how to resolve a conflict in Maine law that resulted from attempts last year to reduce penalties for low-level drug offenses. While one bill passed last year made possession of smaller amounts of heroin and other narcotics a misdemeanor for first-time offenders, another bill retained the felony penalties for the drugs and added the prescription opiate fentanyl to the list.

On Monday, members of the Legislature’s Criminal Justice and Public Safety Committee voted 8-4 to support a bill that would allow prosecutors to pursue felony charges against anyone for possession of heroin, methamphetamine, fentanyl or more than 14 grams of cocaine. The bill, L.D. 1554, would downgrade, however, possession of small amounts of oxycodone pills to a misdemeanor.

Attorney General Janet Mills sought the changes because she said prosecutors need the threat of a Class C felony conviction – punishable by up to five years in prison – in order to force some drug users to enter treatment. Prosecutors do that by sending a case to the state’s drug court system or by using “deferred disposition,” in which accused persons are charged with a felony up front but only end up with a misdemeanor conviction or no conviction if they complete drug treatment and probation.

Mills said that a misdemeanor charge, which carries up to 364 days in jail but often only nets a $400 fine, does not carry enough weight. Misdemeanors are also not “serious enough” to land a defendant in the state’s drug courts, which Mills said have proved effective.

“If this Legislature chooses to lower the penalty from felony to misdemeanor, that’s a message that you don’t consider it to be a serious charge,” Mills told committee members. “And no one on a misdemeanor charge is likely to get into drug court unless they have a lot of other things going on.”

But some lawmakers as well as civil liberties groups and substance abuse providers said a felony conviction can haunt a person for life, leading to the loss of their voting rights, difficulty in landing a job and ineligibility for a host of programs. They also said the get-tough approach to drugs has proved ineffective to combating the nation’s growing heroin epidemic.

“I know that more than ever, police all across the state are coming forward and saying what we don’t need is to put more people into the criminal justice system,” said Rep. Charlotte Warren, D-Hallowell. “What they’ve said to us … is we need treatment and the treatment isn’t out there.”

Warren had proposed keeping first-time possession of heroin and other narcotics a misdemeanor offense but elevating it to a Class C felony upon a second offense. Both Warren’s proposal and the language sought by Mills will now to go the full Legislature, where they are likely to spark additional debate.

Some of the most lively discussion on Monday occurred between Mills and Sen. Stan Gerzofsky, a Brunswick Democrat who said 364 days in jail is nothing to scoff at for most people. Gerzofsky raised concerns about “permanently destroying a life of a person that just might be out for a weekend pleasure” because the person was caught with a small amount of heroin in his pocket.

“Senator, I hope you are not sending a message that people should enjoy a vacation with a little hit of heroin,” Mills said.

Gerzofsky said he doesn’t endorse drug use of any type, but that he understands that some people use drugs.

“I don’t want to treat people differently for the rest of their life because of a mistake they made, especially when they were young,” Gerzofsky said.

Mills replied that a 364-day sentence for a first-time heroin possession charge would be appealed.

“And it will be flipped because it is so far out of range and out of the ordinary,” Mills said.