It is the nature of the beast that the person who holds the office of prosecutor-in-chief is called upon to make difficult decisions. That applies to Bulelani Ngcuka, our own National Director of Public Prosecutions.

A hero of the struggle against apartheid, he has found himself faced with tough decisions involving investigating and prosecuting erstwhile comrades such as Tony Yengeni and Winnie Madikizela-Mandela.

Imbued with a sense of duty, he has not faltered and has been rewarded with convictions in cases that many had thought a former ANC activist would not dare take on. This has been because there are men and women within the prosecuting authority who are dedicated to their work and who conduct thorough investigations before taking matters to court.

In the two cases mentioned above, Ngcuka had to face accusations that he was targeting ANC leaders and that the investigating arm of his directorate, the Scorpions, was designed to fight ANC members. These accusations were muted and were to be expected.

However, Ngcuka and the authority now face an onslaught that is clearly designed to intimidate them into stopping certain investigations. Allegations peddled to the media in the past few months are designed to malign Ngcuka and his office. Last week, an e-mail was distributed that was highly libellous of Ngcuka, his office and a number of his business contacts and friends.

We have no way of knowing who is behind the campaign and therefore cannot point fingers at anyone.

But this much we can say the National Prosecuting Authority is a crucial instrument of justice of the land and is therefore a key pillar in the structures that underpin our democracy.

The attack being made against it and Ngcuka is an attack on the foundations of our democracy and should be condemned. The investigation launched to probe the campaign must be conducted swiftly and those responsible, when found, must face the full wrath of the law.

One of the high-profile investigations under way concerns Deputy President Jacob Zuma's financial adviser, Schabir Shaik, and Zuma himself in allegations of involvement in bribery attempts by the Thomson group in connection with the arms deal.

This touches a particularly raw political nerve, given Zuma's position both in the ANC and in the government.

For this reason, the investigation should be completed quickly so that the cloud over his office is removed or resolved.

We are only about 10 months away from an election and the investigation is creating tensions and allegations of political manoeuvring . Ngcuka is streetwise enough to know this.

We as a nation stand at a crossroads - either we grow into a more stable and democratic society that respects the law, or we crumble under the threats of faceless people hoping to do as they wish.

The choice for all of us must be clear. Politics aside, the law must take its course.

With acknowledgements to Ranjeni Munusamy, Mzilikazi Wa Afrika, Andre Jurgens, Jessica Bezuidenhout and the Sunday Times.