When a retail union targeted an Amazon.com Inc. warehouse in Alabama last year, organizers generally avoided provocation, holding rallies far from the facility and urging placard-carrying activists to stay off the company’s property.

Christian Smalls, an upstart labor leader hoping to unionize Amazon facilities in Staten Island, New York, has tossed that playbook. Over the past couple of years, Smalls has tweeted photos of Amazon consultants he deemed "union busters” and encouraged supporters to disrupt anti-union meetings inside the gigantic JFK8 warehouse. Meanwhile, he staked out the Amazon parking lot, handing out union literature, playing loud rap music and buttonholing workers as they came and went.

Time and again, Amazon says, it warned Smalls he was trespassing. Finally, on the afternoon of Feb. 23, the company called the police, and Smalls was arrested and charged with trespassing, resisting arrest and obstructing governmental administration. (Smalls says a judge adjourned the case for six months and will dismiss the charges so long as he isn’t charged with a crime during that time.)