The Texas Supreme Court has said no to extending the right to a union representative for state workers in meetings with managers. Under current federal laws, employee's right to "concerted activities" under the National Labor Relations Act allows federal and private-sector workers to have a union representative accompany them to meeting with management that could result in disciplinary actions.
A great number of actions can result in an ethical worker winding up on the receiving end of illegal employer retaliation. There are laws in Texas intended to protect employees from these kinds of actions, but they may go unused because individuals don't know about them. Those who suspect they've been the victim of such action can make more informed decisions if they consult an attorney for honest, practical advice.