On April 29, 1911, Massachusetts did what no state had done before: It banned marijuana.

This prohibition sparked a national trend, culminating in the federal criminalization of the drug. Now, more than a century later, voters in Massachusetts stand poised to lead the state in the opposite direction.

When voters go to the polls on Tuesday, they will decide whether to vote yea or nay to Ballot Question 3 which, if approved, would legalize medicinal use of marijuana for patients with “debilitating conditions.”

With a written certification by a physician, patients would be able to purchase a 60-day supply of cannabis from any of the 35 dispensaries sanctioned by this initiative.

A number of other states across the nation are also considering the question of medical marijuana on their ballots, and 17 states and the District of Columbia already allow some kind of medicinal marijuana usage.

While the debate over medical marijuana has provoked strong feelings among both proponents and detractors, it remains to be seen whether or not Massachusetts voters will reverse the decision they made 100 years ago.

PUSHING POT

Polls by The Boston Globe as well as Suffolk University show a majority of voters support the legalization of medical marijuana—the most recent Boston Globe poll suggesting that 63 percent of likely Massachusetts voters are in favor.

Supporters of the initiative argue that marijuana can be very effective in treating individuals with conditions ranging anywhere from glaucoma to AIDS.

In particular, advocates point to evidence provided by organizations like the National Cancer Institute which reports on its website that “cannabis or cannabinoids may have benefits in treating the symptoms of cancer,” and the California Pacific Medical Center whose recent study on animals has shown cannabis could stop the development of cancer cells in humans.

Harvard Medical School professor emeritus Lester S. Grinspoon, the author of “Marihuana Reconsidered,” said that marijuana is “a remarkably benign drug which is capable of doing...remarkable things medically.”

Before conducting research on marijuana’s effects, Grinspoon was a staunch opponent of its use and was “terribly concerned” that the drug would negatively affect his close friend Carl Sagan, the well-known astronomer, who enjoyed smoking marijuana.

However, he now supports the full legalization of both medical marijuana and marijuana for recreational use.

“I have always believed since I had my epiphany that the only way to deal with this substance is to get rid of the prohibition and treat it like alcohol,” said Grinspoon.

The National Organization for the Reform of Marijuana Laws supports state-level initiatives like this one because they do not see full national legalization as a feasible, achievable goal for the near future.