TRENTON — Democratic lawmakers want to divert some nonviolent offenders into drug treatment rather than prison, a notion Gov. Christie made one of his priorities this year.

But two bills winding their way through the Senate and Assembly would use a two-county pilot program to test Christie's belief that forcing people into drug treatment can work. Christie wants to make participation in drug court, a program that keeps drug-addicted offenders out of jail and in treatment, mandatory. It could cost up to $35 million annually to mandate drug court in all 21 counties.

The pilot program is expected to cost $5 million, according to estimates from the administrative office of the courts, which runs the drug court program.

"The governor's program has to be phased in anyway," said Sen. Raymond Lesniak (D., Union), prime sponsor of a Senate bill that would introduce a pilot program to expand drug court. "We don't have the money, we don't have the professionals, and we don't have the facilities" for a statewide expansion.

Christie, a Republican and former prosecutor, budgeted $2.5 million for fiscal year 2013 to develop the mandatory program, which he said would take a year to set up. Sen. Donald Norcross (D., Camden) has introduced a bill that would implement Christie's plan, but it has yet to be heard in committee.

Meanwhile, a pilot program bill sponsored by Assemblywoman Bonnie Watson Coleman (D., Mercer), similar to Lesniak's, also was voted on Monday and now moves to the Assembly Budget and Appropriations Committee.

Lesniak's bill, which is headed to the Senate for a vote, differs slightly from Watson Coleman's by expanding eligibility for drug court so that those who have been arrested on robbery charges can be included. Lesniak, who was the victim of a home-invasion robbery in 2009, plans to further amend his bill during the Senate's next voting session, May 31. He wants to allow prisoners who would qualify for drug court to enter the program retroactively if they wish, something Christie has said he also supports.

If approved as written, Lesniak's bill would cost $8 million: $5 million for the two-year pilot program and $3 million to widen the eligibility. He expects a small additional cost if the program is opened to those already incarcerated who qualify for the program but either weren't offered or previously turned down drug court.

It takes five years to finish the drug court program, but the bills to establish a pilot program cover only two years. Lesniak and Watson Coleman said they would expand the program, provided it's working. Lesniak, for one, worries that those forced into drug treatment could frustrate the group dynamic.

"Those forced into treatment could poison the well for those choosing to go to treatment," he said at an April 3 hearing before the Senate Budget and Appropriations Committee. "I was hoping that by two years, we could make an effective evaluation whether expansion is a good idea, and it works."

Lesniak said he expected that his and Watson Coleman's bills would merge.

Drug court currently enrolls about 4,300 participants. About half of those who qualify for drug court turn it down. Christie has said he believes that many who turn it down are in denial that they have a problem. But treatment providers said refusal also could be because drug court programs don't always allow use of methadone or suboxone, drugs used to help ease withdrawal symptoms for opiate addicts.

Christie spokesman Michael Drewniak has declined to comment on the pilot program bills.

Contact Joelle Farrell at 856-779-3237 or jfarrell@phillynews.com or on Twitter at @joellefarrell.