TL;DR: Threatened or terminated for discussing unions/wages/working conditions in the US? Don’t tell your employer anything, save as much evidence as possible, and contact your local NLRB office.
The National Labor Relations Board (NLRB) oversees enforcement of the National Labor Relations Act (NLRA), which covers certain worker protections in the United States. Under the NLRA your employer cannot punish or fire you for unionizing/discussing unions, or engaging in ‘protected concerted activity’ (which includes talking to other employees about wages/working conditions). Please note that this protection applies to most workers, but excludes government employees and some other kinds of workers. More details here.
If your employer has threatened, punished, or terminated you for discussing these things, or has a general policy forbidding these discussions, you have the right to report it to the NLRB.
THE MOST IMPORTANT THING TO REMEMBER: DO NOT TELL YOUR EMPLOYER WHAT YOU ARE DOING. This only gives them advance warning to cover things up or to build a case for your termination—and even though you can sue for this, you probably don’t want to lose your income in the meantime.
Gather all the physical evidence that you can. Print out emails, take photos/screenshots of handbooks or posted policies. If you want to record conversations, be sure to check your state’s laws about recording consent to make sure you’re legally allowed. You have to report an incident within 6 months of it happening, so don’t wait very long.
You can find your regional NLRB office here. Cases have to be filed with the regional office. Usually they investigate companies, but if you were fired for engaging in protected activities, they can provide you with legal representation to sue. I know someone who did this—they got free representation and won in court.
Decided to write this because I’m tired of typing it up all the time when I see threads that it would apply to. Feel free to copy link and comment it wherever. 🙂
Edit: removed claim that the NLRB can fine employers—this is not currently true, they can get the court to order a company to compensate an individual/group of employees, but can’t impose a fine. There is legislation proposed that would allow for this though, info here.