You may not like employees comparing their bonus checks or bad-mouthing their managers in the break room, but don't even think about trying to silence such off-duty chats. If you do, you could run afoul of the National Labor Relations Act (NLRA), regardless of whether you employ a unionized work force. As two rulings this summer show, the NLRA makes it illegal to ban or punish employee discussions of working conditions, pay, benefits or promotions. Also, several states consider bans on pay discussion a violation of public policy.
While you can't limit such off-duty discussions, you do have the right to set reasonable rules about talking on the job if maintaining a quiet workplace is a business necessity. Example: You can tell employees to discuss nothing but business in front of customers.
Case 1: The National Labor Relations Board (NLRB) struck down a California day spa's policy that said employees would be disciplined for any "negative comments" about managers or co-workers. The board said employees could construe the policy to prevent discussions that might affect their working conditions. (KSL Claremont Resort v. SHERU, No. 32-CA-20417, 2005)
Case 2: NLRB also ruled against a company whose handbook said it "recognizes and protects the confidentiality of any information" concerning employees. NLRB said employees could view that wording as a ban on discussions about pay and work conditions. Such a ban would violate the NLRA. (Cintas Corp. v. UNITE, No. 13-CA-40821, 2005)
Final tip: Several powerful unions recently split from the AFL-CIO and announced renewed efforts to organize service workers. These unions are looking for obvious targets. Banning workplace discussions about pay and wages could quickly put you on the list.