The latest head-count in the Senate offers sobering news for those working to legalize marijuana in New Jersey. Only five senators said yes, from a total of 40.

"We need to slow this thing down," says Sen. Ron Rice (D-Essex), chairman of the Legislative Black Caucus, who is holding public hearings to drum up more opposition.

Great. The criminal prohibition against weed is as crazy and destructive as the prohibition against alcohol in the 1920s, and we just may stick with it.

Both prohibitions taught millions of decent people to ignore the law of the land. They both allowed bad guys with guns to make a fortune. And today, we add a modern twist by imprisoning African-Americans for weed crimes at three times the rate of whites.

But voting to legalize marijuana is a big step, a political risk the tepid careerists in the Legislature might just pass up. The safer option is to dip a toe in the water by ending the criminal sanctions against possession of small amounts, while preserving the criminal ban on sales.

That's known as "decriminalization." And it's emerged as the chief threat to full legalization.

Rice, a former cop, is pushing that half-step. And so are some leading liberals, like Sen. Joe Vitale (D-Middlesex).

"I've spoken to colleagues on both sides of the aisle who are hard and fast no votes on legalization," Vitale says. "But when you say 'decriminalize' they say, 'Ok, maybe.' I think they acknowledge that having some marijuana in small quantities is not a hard-core crime. But they don't want to legalize it. They want to crawl before they walk."

On the surface, that sounds sensible. But let's take a closer look.

Decriminalization is the best news possible for gangs and dealers. They would continue to control the street trade in drugs. And business would boom since buyers would no longer have to worry about being arrested.

Imagine that in the 1920s, we decided to lift the ban on drinking booze, but left the trade to Al Capone, with all his guns. That's what decriminalization would do to the marijuana business in New Jersey.

"It keeps drug dealers on the street and gives them a better marketplace to make money," says Sen. Nicholas Scutari (D-Union), the sponsor of a bill to legalize and tax the trade. "Isn't that the biggest problem, that the corners are overrun by drug dealers? That's my biggest goal, to get rid of them."

Cops say that most drug violence centers on the cocaine and heroin trade, but that some spills over to the marijuana trade as well. If you want a heart-breaking example, read "The Short and Tragic Life of Robert Peace" (Scribner) by Jeff Hobbs, about a Newark kid who gets a full scholarship to Yale, and is later murdered while dealing marijuana in a Newark basement.

"Where there is a demand for drugs, there are territorial issues," says Newark's director of public safety, Anthony Ambrose. "With decriminalization, you still have the drug dealers, and you still have the territories, without a doubt."

What really grates on Ambrose is the time it takes to process all the marijuana arrests, for selling or possessing. That makes the city less safe, he says.

"Last year, we had about 600 arrests for marijuana," he said. "If you put in three hours on each, that's 1,800 man hours that I could have used for something else, like reducing violence, or interacting with the community more."

When his officers are busy with weed, they can't respond as quickly to reports of rapes, burglaries, and muggings.

Ask yourself: Is it worth it?

The Legislature is about to open formal hearings on this. Rice's first public hearing, in Jersey City during the day, was stacked against legalization. He picked the witnesses, selected to reinforce his view, and he says he didn't allow supporters of legalization in the audience to speak. "We ran out of time," he says.

Among his findings: Colorado is witnessing a surge in babies born with brain damage, due to marijuana. I asked him for his source: "You'll find it online, just research it," he said.

Here's hoping the full Legislature does better. We finally have a governor, Phil Murphy, with some common sense on this, so the opportunity is there. Senate President Steve Sweeney (D-Gloucester), is fully supportive, and says he will block attempts to go just halfway.

"I'm not doing that," he says. "That just makes it easier for drug dealers to stay in business. That makes no sense."

Newark Mayor Ras Baraka favors legalization in principle but will support a bill only if it includes efforts to repair some of the damage done by the prohibition. He wants to expunge all marijuana crimes, to devote some of the $300 million to drug treatment and prisoner re-entry and ensure that common people in Newark can open dispensaries without facing barriers, like big fees.

"Newark is split down the middle on this," Baraka says. "There are a lot of people who have seen the effects of drugs who are not going to warm up to this immediately. We need to get to legalization, but there are issues we need to talk about first."

Let's hope the Legislature listens to that good advice and appreciates the damage this prohibition has caused to so many decent people.

Over the last decade, more than 200,000 New Jerseyans have been arrested for marijuana possession, and while few of them land in jail, they face serious sanctions, like fines, loss of jobs, loss of college scholarships, bans from public housing, and suspension of driver's licenses - even if the person was nowhere near a car at the time of the arrest.

The only winners are the dealers -- at least those who don't get caught. Marijuana sales amount to about $900 million a year in New Jersey, and they get all of it.

And who knows? With decriminalization, they may well break $1 billion before long.

More: Tom Moran columns

Tom Moran may be reached at tmoran@starledger.com or call (973) 836-4909. Follow him on Twitter @tomamoran. Find NJ.com Opinion on Facebook.