LANSING, MI -- State Rep. Jeff Irwin, arguing that an ineffective war on marijuana is costing Michigan taxpayers hundreds of millions of dollars a year, this weekend confirmed plans to introduce legalization legislation in Lansing.

The Ann Arbor Democrat highlighted his pending bill in a speech at the 2015 Hash Bash, an annual gathering of marijuana enthusiasts on the Diag of the University of Michigan.

"The idea that marijuana prohibition is effective at doing anything is wrong," Irwin told MLive on Tuesday in a follow-up interview. "It's a put-your-head-in-the-sand approach, and it doesn't work."

By legalizing recreational marijuana, which is readily accessible in many areas despite its illegality at the state level, Irwin suggested that law enforcement officials could spend more time protecting kids from hard drugs, like crystal meth and heroin.

His pending legislation, informed by legalization laws in Colorado and Washington, seeks to create a system for taxable sales of marijuana to adults, licensing of growers and retailers and local control provisions allowing communities to decide whether or how they will allow retail stores.

The bill will not seek to change Michigan's voter-approved medical marijuana law, according to Irwin. If approved, it would allow other residents to grow their own plants for personal use but not sale.

Colorado, which in 2014 became the first state in the country to allow retail marijuana sales, heavily taxes the drug and recorded $8.8 million in revenue for the month of January. The state reportedly applies a 10 percent excise tax on marijuana, a 10 percent state tax on retail sales and a 2.9 percent state sales tax with a local tax option.

Rep. Jeff Irwin, D-Ann Arbor

Irwin's legislation will call for a lower initial tax rate, he said, which he believes will help break up well-established black markets for the drug.

"I think we'll get more legal participation that way. I think we'll do a better job of breaking some of the criminal networks that are currently enriched by the illegal drug trade, and I think we'll do a better job of collecting taxes if we make the barriers to entry for business lower and we tax it at a level that people feel is worth paying in order to engage in a legal transaction," he said.

Still, Irwin estimates that marijuana taxation could generate anywhere between $50 million and $200 million a year in Michigan. Some of that revenue could go to schools, he suggested, or substance abuse treatment programs.

His pending legalization proposal went over well at Hash Bash, but Irwin will face a tougher crowd in Lansing when he officially introduces the bill -- likely later this month.

"I don't favor legalization of another social drug," said Sen. Rick Jones, R-Grand Ledge, a former Eaton County Sheriff. "I'm studying what's going on in Colorado. I see they've had more cases of drugged driving. They've had increased problems, I've read, with psychosis because some people are affected by it, not everyone of course."

Irwin secured two Republican co-sponsors for a marijuana decriminalization bill he introduced last session, but at least one of those lawmakers has decided he will not sign onto full legalization legislation this year.

State Rep. Mike Callton, R-Nashville, said he is worried the legalization push will complicate his long-running effort to expand patient access under Michigan's existing medical marijuana law. He still supports decriminalization, however.

"For the average person, they're going to Hash Bash and they light up a joint while they listen to Tommy Chong, I don't see why they should rot in jail," said Callton, who spoke at the rally on Saturday, along with Chong and Irwin. "If you have someone with a joint in their pocket, I don't think we should clog up our jails."

PENDING PETITION DRIVES, POTENTIAL BALLOT PROPOSALS

Irwin said he is optimistic that small-government conservatives opposed to "nanny state" policies will eventually back marijuana legalization. But he acknowledged that his bill will likely face long odds in the GOP-led Legislature this session.

"Are we going to get to 56 (votes) in the House, 20 in the Senate and the governor by 2016? Probably not, and I think that's why a lot of citizens are pushing for going to the ballot, because they are way ahead of the politicians on this, as usual."

Two separate groups have already filed paperwork with the Michigan Secretary of State allowing them to raise funds for marijuana legalization petition drives, and a third could announce plans in the next month or so.

The Michigan Comprehensive Cannabis Law Reform Initiative Committee, a group led by some of the state's most prominent marijuana activists, was first out of the gate and is hoping to collect enough signatures to put the issue on the ballot in 2016.

The Michigan Cannabis Coalition, which registered as a ballot committee last month and has set up a website, appears to be focused on sending its own legalization legislation to the state Legislature.

The Michigan Responsibility Council, meanwhile, has not yet formed an official ballot committee but is laying the groundwork for a 2016 marijuana legalization proposal and is believed to be well-funded.

The newly-formed nonprofit is "methodically doing its due diligence," according to Paul Welday, a political consultant and former chair of the Oakland County Republican Party, who said the group is looking at the potential economic impact of marijuana taxation and listening to the concerns of law enforcement officials.

"We want to make sure, if and when this is to go forward, we have crossed our T's, dotted our I's and put together a proposal that addresses the major concerns," Welday explained. "If this is moving forward, we want to make sure Michigan sees the upside."

The Responsibility Council is studying legalization models in other parts of the country, including an Ohio proposal that would establish a limited number of grow sites to be operated by investors in that state.

"The one thing we have heard, particularly from folks in law enforcement, is you need to tax and regulate like alcohol -- to a large degree," said Welday.

"Having grow facilities in strip malls is not something people are all that interested in. We do believe this has to be highly regulated and overseen by an organization that will ensure it's done properly and for the benefit of all involved."

Irwin said he prefers more of a "free-market" approach to marijuana legalization. His bill is likely to inform the activist-led ballot committee, whose board and legal team are still drafting language for their pending petition drive.

"Let's put consumers in charge of determining how this market it going to go," said Irwin, suggesting that over-regulation could encourage continued black market activity.

"Let's give local governments the tools to regulate at the local level and make sure these transactions are happening at the appropriate time, manner and place. But otherwise, let's not get too aggressive with the regulation. We know that when we try to grasp this more tightly, it falls through our fingers."

Jonathan Oosting is a Capitol reporter for MLive Media Group. Email him, find him on Facebook or follow him on Twitter.