The Eugene, Oregon Register-Guard newspaper maintained a company policy prohibiting employees from using company communications systems such as e-mail to “so-licit or proselytize for commercial ventures, religious or political causes, outside organizations, or other nonjob-related solicitations.” Employees, however, had not been disciplined for using the e-mail system to invite coworkers to parties, sell sports tickets, etc. Suzi Prozanski, an employee and union president, used the employer’s e-mail system to send three union-related messages to other employees at their work addresses. She was disciplined under the company policy. Did the Register-Guard violate the NLRA in disciplining Prozanski? Explain.