Today is May Day, a.k.a. International Workers Day, an occasion that in the United States once was mainly observed by labor unions. In 2017, reflecting the rise of more informal worker  organizations, civil-rights groups with names like “Rise Up” are behind hundreds of planned strikes, rallies and marches demonstrations around the country in support of labor-related causes like higher minimum wages and relaxed federal immigration policies.

Welcome to the future, saysAndrew B. Prescott, an employer-side labor lawyer with Nixon Peabody in Providence, Rhode Island. With Donld J. Trump firmly installed in the White House, Prescott sees the beginning of an era of more  antagonistic relations between employers and worker groups. And political groups dedicated to causes like fast-food-worker rights, not traditional labor unions, will likely set the tone, Prescott says.

Though May 1 demonstrations may be organized by groups not involved in collective bargaining, lawyers warn employers that today’s activities may still be protected under the National Labor Relations Act.

Writing in Crain’s Detroit Business, employment attorney Nick Huguelet ofDetroit-based Nemeth Law PC notes that the law doesn’t give workers the right to simply skip work on a day like today. But section 7 of the NLRA “protects an employee’s right to engage in concerted activities concerning the terms and conditions of employment or for other mutual aid or protection…this right applies equally in both union and nonunion workplaces and may protect employees from being disciplined for engaging in a strike.”

Though the law”does not protect purely political demonstrations, it can be difficult to show that a job action is purely political,” Huguelet writes. “For example, immigration reform has been found to be sufficiently connected to the terms and conditions of employment, and therefore protected. Because the NLRB for the time being continues to be sympathetic to employee rights, employers should be cautious about imposing disciplinary action on striking employees.”