The 20th Boston Freedom Rally – a giant pro-pot hoedown in the heart of the city – ignited the Common yesterday as a swarm of openly toking marijuana enthusiasts descended on the Hub’s landmark park to enjoy the new chilled-out hemp laws.

The annual rally, also known as Boston Hempfest, and its supporters lauded the Bay State’s new law, effective Jan. 1, 2009, that decriminalized possession of one ounce or less of marijuana, making it a simple civil infraction.

READ MORE: Boston Hempfest grows with lax laws