Twenty-eight female guards were unfairly dismissed by a security company because the client‚ Metrora.
Democratic Alliance chairman Joe Seremane, pictured right, does not want to succeed Tony Leon simply because he is black.
He says those lobbying for him should do so because they recognise his leadership qualities.
"I have not decided whether I will avail myself for the leadership position or not; I am still listening to advice.
"But I will decline should I be asked to stand because I am black rather than because of my ability to lead the party," Seremane said.
Since Leon announced his intention to step down at the party's next congress in May, there have been growing calls for a black leader to take over.
Leon, who has been DA leader since 1994, has failed to shake off the ANC-bestowed racist tag. He announced he was quitting in November.
Seremane said people from across racial lines and political parties have encouraged him to stand for the leadership position.
"But it irritates me when people say I should stand because of the colour of my skin. We need to move away from that mentality," he said.
"I did not wake up one day and decide to join the party because of the colour of my skin. My decision was based on the party's principles and the objective to fight racism in our society."
He said the DA was a party fighting for the benefit of all South Africans and that the number of black members joining was phenomenal.