Reefer madness ends on Monday. Or at least it begins to end as Rhode Island takes its first big step towards ending the era of marijuana prohibition.

The new law goes into effect on April 1, but it’s no joke: possession of less than an ounce of pot will be punishable by a $150 ticket instead of a $500 fine and potential jail time. Decriminalization law was approved by a wide margin last year, with the House voting 50 to 24 and the Senate voting 28 to 6 in favor of eliminating the criminal stigma to getting caught with a small amount of grass.

Legislators will be celebrating on Smith Hill with a press event on Monday at noon and people are encouraged to attend. Others elsewhere are likely celebrate off-the-record.

“Marijuana decriminalization is an important step in the right direction that shows Rhode Island is taking a more sensible approach to marijuana policy,” said Rebecca McCGoldrick, of Protect Families First, a group advocating for the end of pot prohibition. “Regulation is the next step because it will help undermine the illegal marijuana market and improve public health and safety.”

McGoldrick might get her wish. A bill before the General Assembly this year would “tax and regulate” rather than outlaw and enforce the marijuana market. Out of state experts, such as Rolling Stone magazine and the Marijuana Policy Project, predict that Rhode Island will be among the next states to legalize marijuana.

While the bill hasn’t gained much attention this year, anything can happen during a session in which the state legislature is obviously engaged in much horse trading.