“We cannot overprice and overtax the legalization of marijuana, we can’t, we don’t want the black market to continue to dictate the flow of this substance,” said Hampden County Sheriff Nicholas Cocchi at the final State House hearing before lawmakers deliver their rewrite of the marijuana legalization law.

But Monday’s testimony underscored the fact that it’s a delicate balancing act between overtaxing and undertaxing.

Cocchi and other sheriffs told the legislators they want five percent of the pot revenue earmarked for a marijuana addiction treatment fund, and noted that a large percentage of their inmates are drug addicts in need of treatment.

“Not everyone will smoke responsibly much the same way many people do not drink responsibly,” said Sheriff Patrick Cahillane of Hampshire County. “This will lead to additional individuals ending up in the correctional system in need of treatment.”

The five percent would be added to the current 6.25% sales tax, the 3.75% excise tax and a two percent local-option tax would push the tax bite on marijuana to 17 percent, comparable to what other legal-pot states extract, but nearly double what voters approved last November.

At the hearing, medicinal pot users argued for keeping prices down to promote access to medicinal treatment. And the complexity of the issues raised by the new law was underscored by a convicted felon’s plea for scrapping its ban on drug offenders working in the marijuana industry.

“I’m looking to ply my trade, I’m a marijuana grower, I’m good at what I do,” said Sean Berte. “I don’t want to be left out.”

In fact, it was argued, past offenders should be at the head of the line for a cut of the take.

“Because many of them are victims of this failed war on drugs, I believe they should have some type of preference in being part of one of the teams relative to ownership,” said Boston City Councilor Tito Jackson. “It would be poetic justice.”

Lawmakers say they’ll have a revamped law ready for debate and voting by June, with the opening of legal pot stores now set for July of 2018. Expect some intense wrangling over the high stakes and complex issues involved.