Employment law update – Lock-out in response to a strike: Distinction between a terminated and suspended strike

July 1st, 2023
National Union of Metalworkers of SA v Trenstar (Pty) Ltd (2023) 44 ILJ 1189 (CC)


Section 76(1)(b) of the Labour Relations Act 66 of 1995 (LRA) reads:

‘An employer may not take into employment any person –

(a) …

(b) for the purpose of performing the work of any employee who is locked out, unless the lock-out is in response to a strike.’

An offensive lock-out is when an employer, in the absence of the employees going on strike; prevents employees from entering its premises in an attempt to force them into accepting a demand concerning a matter of mutual interest. Under these circumstances, the employer, in keeping with s 76(1)(b), is not allowed to employ replacement staff.

A defensive lock-out is when an employer locks out employees, in response to the employees engaging in strike action – in which case and as per the above section, the employer is allowed to employ replacement staff.

The question before the apex court was whether an employer, who embarks on a defensive lock-out, can continue to employ replacement staff once the striking employees decide to suspend their strike and wish to return to work. Put differently does a defensive lock-out change to an offensive lock-out, when striking employees decide to suspend their strike action and under which circumstances, replacing labour is not permitted.


The National Union of Metalworkers of South Africa (NUMSA), on behalf of its members, demanded the respondent employer, Trenstar, give its members a once off gratuitous payment of R 7 500. Once Trenstar refused, NUMSA referred a mutual interest dispute to the Commission for Conciliation, Mediation and Arbitration (CCMA). Conciliation failed after which NUMSA, on 23 October 2020, gave the employer notice of its intention to strike beginning 26 October 2020.

The strike continued for a month whereafter the union’s attorney, at 1:25pm on Friday, 26 November 2020, wrote to the employer and advised that the union had decided to suspend its strike with effect from end of business that day and that its members would be returning to work on Monday, 23 November. In the same correspondence, it was clearly stated that decision to suspend the strike should not be construed as a withdrawal of the demand.

In reply, sent shortly after receiving the above letter, the employer wrote to the union and informed it that the employer gives 48 hours’ notice of a lock-out to begin at 7am on Monday, 23 November, the purpose of which being a demand that the union and its members drop or waive the demand of R 7 500 gratuitous payment. The employer went further to record that the lock-out was in response to the union’s strike action and, therefore, s 76(1)(b) was applicable.

NUMSA approached the Labour Court (LC) on an urgent basis seeking an interdict preventing Trenstar from employing replacement labour for the duration of the lock-out. NUMSA argued that when the lock-out commenced, the strike had ended and, therefore, the lock-out was an offensive lock-out, following which, replacement labour was not allowed.

Trenstar argued that NUMSA had not withdrawn the strike or the demand but merely suspended it after which it could reinstate the strike at any time.

The LC dismissed the application on the approach that the lock-out was called for in response to the ongoing strike and hence s 76(1)(b) found application. The LC held further that the fact that the lock-out began when the strike was suspended was not a determining factor in the dispute.

Pursuant to the court’s judgment, NUMSA abandoned its demand and the lock-out ended.

NUMSA nevertheless appealed the decision of the LC. The Labour Appeal Court declined to entertain the appeal on the basis that the dispute was moot.

NUMSA, thereafter, approached the Constitutional Court (CC).

The CC found that it would be in the interest of justice to grant leave to appeal, more so, considering the conflicting judgments handed down by the LC regarding s 76(1)(b).

Before the CC, NUMSA argued that an employer’s right to employ replacement labour, should end when a strike ends. This interpretation of s 76(1)(b), according to NUMSA, would have the least impact on the constitutionally guaranteed right to strike. Such an interpretation accords with the literal and common sense meaning of the phase ‘in response to a strike’ as set out in the section. Once a strike ends an employer may continue a lock-out, but this would be an offensive lock-out, following which the prohibition of replacement labour must apply.

Trenstar persisted with the distinction it drew between a suspended strike and a strike that has terminated. It argued that its notice calling for a lock-out was issued while the strike was ongoing, despite the announcement of the suspension of the strike being already made at the time. Therefore, factually, the lock-out was in response to a strike. Trenstar continued to argue that the union only suspended the strike and could, at any time, reinstitute their strike action. If the union was correct on its interpretation, then each time an employee issued a 48-hour notice for a lock-out in response to a strike, all the union had to do was to issue a notice suspending the strike immediately prior to the expiry of the 48-hour notice period. This according to the employer would frustrate the purpose of a defensive lock-out.

The court began first to address the distinction made by the employer that the strike was suspended and had not terminated. On this issue the court held:

‘If employees are not refusing to work and are not retarding or obstructing work, they are not on strike, and no strike exists. This is the ordinary meaning of the words used in the definition of “strike”. If the employees were previously refusing to work for a prescribed purpose, but are no longer refusing to work, there is not a strike. The fact that the grievance or dispute underlying the prescribed purpose remains in existence does not mean that the strike has not come to an end; a demand unaccompanied by a concerted withdrawal of labour is not a “strike”’.

The court went further to find that the employer conflated an unconditional right to strike with a strike. Once a dispute has been conciliated and at the expiry of the statutory notice period, a union acquires the right to strike. However, it is only when the employees stop work, that the strike begins. During the period of suspending the strike, there is no strike, rather an unconditional right to strike at any time.

The court summarised its finding on this score as follows:

‘The position in this case, therefore, is that the strike ended at 17h00 on Friday 20 November 2020. A few hours earlier, but after being notified that the strike would so end, Trenstar gave notice that it would commence a lock-out at 07h00 on Monday 23 November 2020. Trenstar in fact implemented the lock-out as notified. As from the Monday morning, the employees’ absence from work was due to a lock-out, not a strike. Trenstar did not reject the tender of services as unacceptable or incomplete. Instead, it excluded the employees from the workplace in terms of a lock-out despite their tender of services.’

In further support of its findings, the court turned to the wording of the section under discussion. Section 76(1)(b) allows for replacement labour when the lock-out ‘is’ in response to a strike. The word ‘is’ denotes present tense and not past tense. Stated otherwise, replacement labour is permitted because of an ongoing strike and not because of a strike that ended.

The CC set aside the order of the LC and replaced it with an order, which would have prevented the employer from employing replacement labour as from 23 November 2020. No order as to costs was made.

Moksha Naidoo BA (Wits) LLB (UKZN) is a legal practitioner holding chambers at the Johannesburg Bar (Sandton), as well as the KwaZulu-Natal Bar (Durban).

This article was first published in De Rebus in 2023 (July) DR 33.