The night I reduced Bernie Grant to tears

Channel Four launched its winter season last Wednesday and highlighted a documentary series, White Tribe, which I wrote and presented, to be broadcast in early January.

In this world of dinosaurs, soaps, sport, gardening and cookery, serious documentaries have certainly been on the wane. But Channel 4 does still provide an oasis for serious television.

It hasn't been easy. Jeremy Isaacs tells the tale of his visit to a Home Office minister to outline his plans for the new channel just before its launch in 1982. The minister seemed rather pleased about his plans, with the one stern injunction: "As long as you don't have that man Darcus Howe on the screen."

Isaacs promptly employed me. There were difficulties still. London Weekend Television was given the commission to produce Black on Black, a multicultural magazine programme, and Channel 4's commissioning editor suggested that I present it. I was given a screen test in a dark basement in the West End. The verdict? I was not up to it, the camera did not like my face. I got a consolation prize, though. They appointed me a consultant to the programme. In the space of nine months I was consulted once - on the Grenada revolution, when John Birt's young turks (he was then director of programmes at LWT) did not know that St George's was the capital of Grenada, soon to be invaded by American troops.

Later, Black on Black was replaced by Bandung File, which Tariq Ali and I produced. Before we were given the commission, Isaacs sent for us. We were ushered into the headmaster's office and asked: do you belong to any political organisation? We both replied in the negative. Tariq had just been rejected by the Labour Party, and the International Marxist Group had seen better days. I learnt one thing from Isaacs that day. In the field of current affairs, you cannot serve two masters. That principle has long flown the coop. Today, so much of current affairs output seems to amount to little more than Labour Party broadcasts.

I had not set my eyes on a television set before arriving in England some 40 years ago, but I soon settled into a diet of Panorama, Hancock's Half Hour and Coronation Street. It was the vehicle through which I discovered England. Earlier, at home in Trinidad, I formed my very first impressions through the radio: "This is London calling, this is the voice of the BBC." Promptly at 4pm, we were all summoned by my mother to sit quietly and listen to some news broadcast delivered with such gravitas that I spent my childhood in great fear of ever missing the daily summons. Even today, I feel duty-bound to watch Channel Four News.

So it is not surprising that David Frost's famous interview with the insurance fraudster Emil Savundra made such a strong impression on me. He literally destroyed his reputation. Soon after, Savundra was arraigned and sent to prison. Many years later I suggested an idea to Channel 4, which eventually led to Devil's Advocate. It had its origin in that Frost interview.

I could never repeat that Frost performance, but there was one moment I remember with a certain impish satisfaction. The black Labour MP Bernie Grant had reportedly made a statement about repatriation and I was horrified. We invited him to the "hot seat" to be examined, and I asked my researchers to comb England for a tape of a speech where Grant had mentioned the word.

We found one. Grant entered the studio and promptly denied ever using the word. I urged him to accept that he had. "Have you a tape or something?" he asked. "Forget the tape, Bernie, and accept that you used the word 'repatriation'." "No I did not." "If I have a tape, shall I play it?" "Yes," he replied confidently. The tape rolled, and then came the final punch: "Is that your voice?"

Bernie wept backstage. He felt that he was finished as a politician. He was wrong. Television had by then lost its power.