If the Supreme Court were to uphold the Massachusetts law, it’s not hard to imagine businesses lobbying to create zones where union members are not allowed to speak, but workers for the business are. Businesses could use the same logic used in McCullen: the picketers are disrupting business and upsetting customers. So, government, please silence them—even though they are standing on a public sidewalk.

Potter described how liberal activists have made this mistake before. He said, “Back in the late 1990s…Planned Parenthood was using RICO statutes against anti-abortion protestors. A lot of civil rights people were saying this is going to come back around to us and sure enough RICO has been used against animal-rights protestors. The [lawsuits] have failed, but it costs mountains of cash to defend against.”

In an interview, the First Amendment lawyer Floyd Abrams—who is a supporter of abortion rights—described the Massachusetts law as being “as bad as first amendment cases have gotten in a while.” He said of the liberal groups supporting the law, “They undervalue the First Amendment…and substitute political liberalism” as their guiding principle instead.