A state panel heard from a parade of experts Thursday as it began studying whether to legalize marijuana in Indiana or reduce criminal penalties on small amounts of the drug.

The experts shared a common message: The prohibition against marijuana use in the United States has failed, and Indiana and its citizens stand to benefit from changing the law.

"The public recognizes that our marijuana laws have done more harm than good," Daniel Abrahamson of the Drug Policy Alliance told the Indiana Legislature's Criminal Law and Sentencing Policy Study Committee.

Lawmakers have approved medical marijuana in 16 states and the District of Columbia. They have eliminated penalties on small amounts of marijuana in 13 other states.

Abrahamson said those changes have not met with negative consequences such as an uptick in marijuana use. And he said there is nothing standing in the way of Indiana changing its law as other states have.

"The federal government cannot require states to make marijuana illegal," he said. In no instance, he said, has a state changed its mind and "re-criminalized" marijuana after decriminalizing personal use.

Noah Member of the Marijuana Policy Project said marijuana use is widespread despite being illegal and that laws against possession ruin people's lives by sending them to prison for using a substance he said is safer than alcohol.

Member suggested marijuana should be regulated by the state much like alcohol. He said states that have legalized medical marijuana have seen no increase in teen use of the drug.

Abrahamson estimated Indiana could raise $44 million a year in sales taxes alone if it regulated and taxed marijuana.

Democratic state Sen. Karen Tallian of Ogden Dunes successfully pushed lawmakers to study the issue. She says the state has "draconian" marijuana laws.

Republican Gov. Mitch Daniels has said he would like to wait and see what the panel finds before taking a position.

Indiana lawmakers this year banned the sale and possession of synthetic marijuana, also called spice, which sometimes has dangerous side effects.