Last Friday, DA MP Masizole Mnqasela was acquitted on charges of raping a 17-year old girl at his home in the Pelican Park Parliamentary village in May 2010.

I had been expecting this outcome after following the case with profound concern and interest from the start. Since the allegation first surfaced in June last year, public commentators have described the case as a "litmus test" for the Democratic Alliance.

Editorial writers have criticised me for failing to suspend Mnqasela pending the outcome of the trial. There have been hostile questions in Parliament. The DA has been accused of "double standards" for failing to apply to ourselves the same standard we demand of the ANC.

On the face of it, these are valid criticisms. So why did I, and the DA, seemingly fail to "practice what we preach"?

The reason is that, from the start, I was convinced the rape allegation was a "set-up". This suspicion was confirmed as the trial unfolded, over many months, costing Mnqasela hundreds of thousands of Rands and incalculable personal trauma.

The obvious question is: on what basis did I make the assumption of a "set-up"?

The answer lies in the context in which this allegation arose, and the case unfolded. The rape charge was not the first time Masizole has faced spurious and malicious charges. Hopefully, it will be the last.

It is worth, briefly, recounting the story from the beginning.

During his schooldays, Masizole was an ardent ANC activist in Khayelitsha, holding executive positions in various structures. In 2002, aged 21, he had become so disillusioned that he left the organisation. But he went a step further, which was very unusual for young ANC militants at the time: he joined the DA. I was, back then, the DA MP responsible for building DA branches in Xhosa-speaking communities. I drew Masizole into our small task team, and quickly recognised his strength in grassroots organisation.

With fearless determination he helped recruit members and build branches in extremely hostile territory. Over the years we witnessed the harassment of our members: arson attacks on their houses; kangaroo court trials for the "crime" of joining the DA; arrests on spurious charges (often on a Friday so that the "accused" would remain in jail all weekend until the charges were withdrawn on Monday). There was no end to the dirty tricks.

I vividly recall a visit I paid to the police station in Langa to demand the release of one of our activists, Mrs Mambele Makaleni, who had (again) been arrested on a Friday afternoon on a charge of allegedly stealing R5 (yes, five Rand). I protested that she was being politically persecuted, at which the officer on duty responded: "What do you expect if you try to organise for the DA in an ANC area?"

Shortly afterwards I remember trying, in vain, together with the small DA Langa branch, to prevent ANC activists burning down Mrs Makaleni's shack at 03h00 one morning -- while the police stood by and watched.

This was the context of the time. Many policemen had no idea that their role was to defend everyone's rights and freedoms under the Constitution. Masizole was one of a small handful of people prepared to stick their necks out, and pay the price.

In 2003, a vacancy arose in the DA's caucus in the Cape Town City Council. I persuaded Masizole to apply. He faced the DA's electoral college on Saturday 18 October 2003, and succeeded in winning the nomination. The next evening, I visited him at his mother's Makhaza home to help him plan for his first council meeting scheduled for Wednesday, 23 October. As I drove away, I was ambushed near his home, and shot through the door of my car. At the time I thought it was merely an attempted hijacking (the police never pursued the investigation).

Three days later, as the DA's first Khayelitsha councillor proudly arrived at the Chamber, Masizole was confronted by the police and arrested on a charge of assaulting a former girlfriend. What should have been a day of triumph turned into trauma. He protested his innocence, but the "default" sympathy lay with the complainant. A few days later, the woman dropped the case, admitting that she had been used in a smear campaign by the ANC councillor who did not want Masizole organising in his ward. The complainant was charged with defeating the ends of justice, but like so many similar cases, it went nowhere. Masizole was never even asked to make a statement. He told me at the time: "This matter will never go to court. It would expose too much about the ANC's strategy and about the role of the police in Khayelitsha."

A few weeks later, around November 2003, Masizole and I organised a public meeting in the Desmond Tutu Hall in Makhaza, to introduce him formally as the DA's PR councillor in the area. We attracted about 60 people to the meeting -- hardly a threat to the overwhelmingly powerful ANC. As the meeting started, an ANC protest march descended on the hall. Listening to the slogans, I realised that matters were unlikely to remain peaceful for long, so I phoned the police.

Before the police arrived, scores of activists in ANC T-shirts pushed open the doors and poured into the hall. Chairs and other projectiles were hurled around. People ran for cover. Masizole and I were dragged out of the meeting and across a courtyard. The protestors tried to put me into a waiting taxi but, with the help of some supporters, I managed to resist. Across the square I saw that Masizole was surrounded by the mob. He drew his firearm (which until then I did not know he possessed) and fired a warning shot in the air. The police arrived. And, to my amazement, they arrested Masizole!

After extensive protestations from me, the police also arrested the main ANC ringleader who had encouraged the assault. I laid a charge against Ms Noxolo Xawuka, the woman who had assaulted me. She turned out to be the girlfriend of the ANC councillor in the area. I learned later that her name had been replaced on the charge sheet by a Ms Nolitha Nyoka and, after one court appearance (at which the matter was postponed), the case mysteriously evaporated. When I enquired I was told the docket had been lost.

In the years that followed, many DA members faced severe harassment -- the worst of which was an arson attack on the home of one of our key activists during which two children were killed. Instead of combing the area for evidence, (which included traces of the flammable liquid poured through the window onto the curtains), the police levelled the site and removed the remains of the dwelling. Despite my efforts, and complaints to the Independent Complaints Directorate, nothing came of the matter.

In November 2006, Masizole was again arrested at a Gugulethu restaurant, and held in police cells for 8 hours. Although he is a teetotaler, he was charged with "drinking in public". His arrest attracted widespread media coverage. When this charge was withdrawn, he was re-charged for allegedly "obstructing the police in the execution of their duties". This case was later also withdrawn. He then successfully sued the police for wrongful arrest and was awarded damages of R100 000.

The harassment abated for a while and DA activists, including Masizole, continued to organize in Khayelitsha with considerable success. He became an MP in the 2009 election, with Khayelitsha as his constituency, succeeding me.

When the bombshell of the rape charge dropped in June 2010, I immediately called him in, in my capacity as DA leader. He knew how serious the charge was and that he would be expelled from the party and lose his job if convicted. He gave me a solemn pledge of his innocence. He told me that, on the night in question, a former girlfriend had called him. She and two friends had been out drinking and had run out of money. They wanted Masizole to fetch them and buy them food and more alcohol.

As he was recuperating from surgery, he told them that he could not take them out for the evening, but agreed to bring them to his house where they could eat the leftovers of a braai. Masizole had three other visitors at his home, apart from the girls, all of whom stayed overnight. The following morning Masizole left for work early, after making arrangements with a friend to take the girls home when they woke up. The girls left during the course of the day -- after eating breakfast and helping themselves to an expensive bottle of whisky. Later that day, his former girlfriend laid the charge of rape. Masizole was arrested a week later.

I asked him what the girl's motive could be. He replied: "I think she expects me to pay her to make this go away. There may also be a political motive. But I will not be blackmailed."

I then asked whether I could discuss the matter with his attorney, and he readily consented. I asked the lawyer (who has represented both Masizole and me in previous matters) a direct question: is Masizole being framed again? His one-word answer was unambiguous: "Absolutely".

He told me that, apart from the consistency of Masizole's version of events (corroborated by the other friends in the house that night) he had a medical specialist's certificate confirming that the surgery, from which Masizole was recuperating, would have made sex impossible at the time. Masizole had also given a blood sample for DNA testing to determine whether it matched the "fluid" detected during the girl's medical examination after she laid the charge. As the lawyer delicately put it: "The examination detected fluid, but it was not Masizole's". The girls even invented stories about being locked up in the bedrooms -- a lie that was exposed when the Pelican Park caretaker testified that the internal doors in the house do not have keys.

With Masizole's permission, I also discussed the issue with the DA's Federal Council. We concurred that, in the circumstances, we had to give him the benefit of the doubt. In such matters, we agreed, it was necessary to evaluate a case on its context and circumstances. We could not immediately suspend a public representative charged with a crime, even one as serious as rape, without applying our minds in this way.

If we did, it would open us up to serious abuse by our opponents. Imagine, for example, the crucial run-up to an election -- after the deadline for nominations, but before voting day. It would be the easiest thing, during this period, for the ANC to trump up charges against DA candidates, forcing us to suspend them, but preventing us from nominating alternates.

When I told Masizole about the Federal Council decision, I also made it clear: if you are found guilty, it will be the end of the line for you in the DA. He expressed confidence that he would have a fair trial and be acquitted, but the strain was clearly draining him.

After repeated court appearances and postponements, each accompanied by media exposure, judgment day -- 29 July 2011 -- finally arrived. The magistrate, Kay Pillay, acquitted him on the basis that the evidence of the three girls was contradictory, improbable -- and fabricated. Not for the first time, I had cause to give thanks for the independence of South Africa's courts.

But the same, unfortunately, cannot be said about the police investigation. There are many unanswered questions, for example: why did the police only take statements from the three girls, and not from the three other visitors in the house that night? I intend to use the police investigation in this matter as a test case for the "oversight" powers of the provincial government. At root, we need to understand why the police in some areas have so zealously pursued bogus charges against the DA, while ignoring serious and substantiated charges against the ANC.

Masizole, who is now 29 years of age, also has some introspection to do. In the moral universe in which I was raised, it is not appropriate for a man in his position to have a relationship with a 17-year old girl, even with her consent. But this is not a crime. And he has also learnt the hard way not to fetch young women who have run out of cash after a drinking binge (and then accommodate them overnight). Life has hard lessons for all of us -- but very few of us have to learn them in the full glare of public scrutiny. Politics is forbidding terrain. How many people could survive having every detail of their lives publicly scrutinized? What are the implications for one's family?

Above all, this case demonstrates once again how crucial it is to maintain and build the independence and professionalism of our criminal justice system and all its institutions. Despite some far-reaching rot, our courts can still generally be relied upon to ensure a free and fair trial, if all the facts are brought before them. This often depends on good legal representation, which is unavailable to many. It is our duty to extend this right to every citizen, and to preserve those institutions that remain untainted by political influence. The future of democracy depends on it.

This article by Helen Zille first appeared in SA Today, the weekly online newsletter of the leader of the Democratic Alliance.

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