Yes. The Supreme Court ruled in the 1975 case National Labor Relations
Board v. Weingarten, Inc. that employees in a unionized organization
have the right to union representation during an investigation interview if the employee reasonably believes that the meeting may result in disciplinary action. Although you’re not required by law to tell unionized employees that they have the right to the presence of a union representative, you may still wish to do so. If that is the case, you should tell your subordinate that the meeting may result in discipline and that she has the right to have a union steward present.

If a union steward isn’t available at the time you’re planning onhaving the meeting, you should reschedule. You might even send the employee home with pay pending the meeting if the employee’s actions were egregious. Forcing a meeting when a steward is unavailable may only give the union a separate cause of action against you.

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That being said, it may be a wise management practice to inform unionized employees about their Weingarten rights even if they don’t voluntarily request a steward’s presence. First, it’s a fair and open way to manage your employees. Second, understand that managers often have fairly defined views of unions: They either feel that management should cooperate with unions in the employees’ best interests or believe that management’s responsibility is to minimize the union’s influence over the organization.

As a result, corporate cultures may develop that are either cooperative
or hostile vis-a`-vis union intervention. The pros and cons of union involvement in companies’ management practices go far beyond the scope and purpose of this book. Regardless of your feelings, it’s important to recognize that failing to recognize Weingarten rights or relying on formalities may only aggravate the situation.

Therefore, in this author’s opinion, reminding an employee of her right to have a steward present at a disciplinary meeting, even if she doesn’t ask, demonstrates to your workers and to the union that you’re fair and objective in your management practices. That’s an important perception to preserve regardless of your feelings regarding union activities. In addition, such open communication in the workplace may minimize employees’ needs for union membership in the first place.

Taken From : The Hiring and Firing Quention and Answer Book