On 18 April 2023, the Constitutional Court handed down judgment in National Union of Metalworkers of South Africa (NUMSA) v Trenstar (Pty) Ltd[1](Trenstar). It had to consider the interpretation of section 76(1)(b) of the Labour Relations Act (LRA), which prohibits employers from using replacement labour during a lock-out unless the lock-out is in response to a strike.

The underlying dispute between NUMSA and Trenstar, the employer, arose from NUMSA’s demand for a gratuity payment for its members.

NUMSA issued a notice of its intention to strike and embarked on the strike, which continued for several weeks. 

On the same day that NUMSA gave notice that the strike would be "suspended", Trenstar issued a lock-out notice stating that its lock-out was in response to the strike action, and it intended to use replacement labour for the duration of the lock-out.

NUMSA sought to interdict Trenstar from using replacement labour during the lock-out by bringing an urgent application in the Labour Court, which was dismissed. The Labour Court found that Trenstar had a lawful right to use replacement labour in the circumstances. In the intervening period, NUMSA abandoned its demand for the gratuity and the lock-out ended. However, it still appealed to the Labour Appeal Court (LAC), which dismissed the appeal, stating that the matter was moot.

NUMSA persisted, and the case was referred to the Constitutional Court. At the Constitutional Court, NUMSA argued that the interpretation of section 76(1)(b) is a point of law of general public importance, which impacts the efficacy of strikes and should be clarified. The Constitutional Court noted the definition of "strike" in the LRA, which states that for there to be a strike, there must be a concerted withholding of labour for a specified purpose. Having regard to the definition, the court found that "if employees are not refusing to work and are not retarding or obstructing work, they are not on strike". If the employees were previously refusing to work for a prescribed purpose, but were no longer refusing to work, there was no longer a strike in respect of which it is possible to respond to by way of a lock-out. 

The terms "termination" or "suspension" of a strike, although used in collective bargaining parlance, are not defined in the LRA and their meanings may depend on the context. The court noted, however, that employees who tender their services by "suspending" a strike, rather than "terminating" it, are indicating that they reserve the right to strike again in respect of the demand. It is also important to distinguish between a strike and an unconditional right to strike. If the dispute was the subject of unsuccessful conciliation, and if 48 hours' notice of the strike was given, there is an unconditional right to commence a strike. If striking employees later return to work by "suspending" their strike, they would not waive the unconditional right to strike which accrued to them. During the period of suspension, there is no strike as envisaged by the LRA, only an unconditional right to strike.

Turning to the interpretation of what it means for an employer to lock out employees in response to a strike, the court considered two interpretations. The first was that a lock-out could be understood in relation to what caused it to be implemented. However, the second interpretation focuses on the present tense "is" in the expression "unless the lock-out is in response to a strike". The court stated that the use of the present tense lends support to the idea that the strike must still actually be under way at the time of the lock-out for the lock-out to be in response to a strike.

The Constitutional Court was guided by the need to maintain an even balance of power in collective bargaining processes. To allow an employer to persist with a lock-out when it may use replacement labour, long after striking employees had tendered their services, may be punitive. This, in turn, would significantly deter employees from exercising their constitutional right to strike, undermining the balance of power that the LRA seeks to establish in line with international standards.

Accordingly, the right to use replacement labour lasts only as long as the lock-out lasts, and it might be necessary for the lock-out to have started while the strike was still under way to trigger the exception in section 76(1)(b) of the LRA.

This judgment highlights the importance of understanding the distinction between a strike and the unconditional right to strike, which upholds the constitutional right of employees to strike. The employer's right to lock out does not enjoy the same protection.

Employers who deliberate about or who have in fact locked out employees in response to a strike and utilise replacement labour should remain extremely vigilant about the on-the-ground realities and status of a strike, before being seduced by the semantics of whether a strike is said to be "suspended" or "terminated".

Written by Kenneth Coster, Partner & Amy King, Knowledge Lawyer from Webber Wentzel