Walmart has admitted to taking illegal action against pro-union employees in some of it’s California stores. After a prolonged lawsuit, the retail giant signed an agreement last month with the workers’ advocacy group, Our Walmart, acknowledging that their 2010 dress code banning union buttons was a violation of national labor law. The company also admitted to taking disciplinary action against six workers who participated in a peaceful protest in 2012. An administrative law judge ruled against Walmart on these counts in 2016, but the company appealed the decision which allowed them to avoid rescinding the disciplinary actions and dress code until April of this year. Walmart must now post notices in its Placerville and Richmond stores about the reformed dress code.
See "Walmart to Permit Union Insignia After Settling Employee Dispute", Matthew Boyle and Jef Feeley, Bloomberg, May 11, 2018