Changing the state's juvenile justice system required a new way of looking at criminal responsibility for 16- and 17-year-old offenders. And it will also require money. Law enforcement officials on the county level worry the cost will have an impact on how the law will be carried out. 

"The ability, I'd say, for the resources to be available to the counties to be able to implement Raise the Age may be something we have to continue to talk about," said Assembly Speaker Carl Heastie.

Next year, 16-year-olds accused of certain offenses won't be treated as adults. By October 2019, the same will be true for 17-year-olds. So, county governments will need to find new facilities for these young inmates and provide transportation. 

"One of the major concerns is just those variables regarding housing and transportation," said Albany County Sheriff Craig Apple. "That's a big dollar amount we're talking about here. If you're building juvenile jails around the state, you're talking about hundreds of millions of dollars."

In addition to constructing or finding new facilities to hold juvenile inmates separate from the adult population, county governments will need to hire probation officers to handle the influx of cases.

"Almost assuredly, there will be a need for additional probation officers because probation officers will become the front line contact -- when the bill is fully implemented --  for all 16- and 17-year-olds charged with every crime that's covered, which will be every misdemeanor and felony, other than vehicle and traffic," said Washington County District Attorney Tony Jordan.

Jordan is the DA of a rural area that covers a wide region near the Vermont border. While New York City is already equipped in some cases to handle the change under Raise the Age, a rural county with a small budget may have a more difficult time.

"They have facilities that exist to accomplish housing the offenders that will fit. We simply don't, and so that's going to be a major expense," Jordan said.

Raise the Age advocates, however, say there is a benefit to the law on a financial basis: Over time, other states that treat 16- and 17-year-old offenders as minors and kept them out of prison have found a reduction in repeat offenses.

"From a longer-term outcome, they say a lot of savings, a lot of savings," said Families Together CEO Paige Pierce. "The cost of processing kids through the adult criminal justice system and sending them off to state prison is greater than providing like alternatives to detention and getting them the services that they need so they don't recidivise."

It's a sentiment echoed by Governor Andrew Cuomo's administration, which championed the law. 

"So we don't envision that we will see significant costs with Raise the Age," said Alphonso David, top counsel to the governor. "In fact, we anticipate based on what we've seen with almost every other state, there will be a significant decrease in taxpayer dollars with Raise the Age."

David insisted, meanwhile, county governments will be paid back for any expenses they incur when implementing the law.

"To the extent that a county or a municipality is going to incur additional costs associated with raising the age, the state has agreed to compensate or reimburse the municipality for that cost," David said.

But those who advocate on county government issues in Albany aren't convinced.

"Clearly, the reimbursement issues by the state are very vague, very confusing to local government officials," said Association of Counties Executive Director Stephen Acquario. "To stay under a state-imposed property tax cap at the same [time] most of those state mandated costs are rising putting pressures on counties to receive reimbursement, that in itself is a challenge."

Then there are those who supported Raise the Age, but feel there were too many compromises in the negotiations. Some advocates have said they want to see changes made the law, even as it's being implemented. The governor's office urged caution.

"I think that's somewhat premature," David warned. "I understand the question you're raising, because I've heard from advocates and stakeholders that there are additional tweaks that they may want, but I think it's premature to raise them, because we first have to implement the law."