Bertrand Tavernier is a director who can claim that his films (including his latest, 'Holy Lola') have changed things. The enthusiastic and still angry veteran talks to Lara Marlowe in Paris

Bertrand Tavernier lives and breathes cinema. In the 20 years since Martin Scorsese anointed him "France's leading director", Tavernier has continued to produce a stunning number and range of films, as well as heading the Lumière Institute, which preserves France's cinemato-graphic heritage in his native Lyon, and playing a major role in the French directors' guild.

Tavernier is a big, scruffy, white-haired teddy bear of a man. Like Lulu, the maverick drug squad cop in L.627 (1992), he might say: "I feel as if I know things better when I film them." Comparing himself to Roddy, the character in Death Watch (1980) who has a camera implanted in his eye to film secretly the death of a terminally ill woman, he has said: "You can witness something sad or close to you, and suddenly think: 'My God, that would be great in a film.' It's horrible. I did that a couple of times and felt ashamed."

But Tavernier does not prey on human emotions, he gives expression to them. Dominique Sampiero, the co-writer of his latest film, Holy Lola, has described Tavernier as "hyper-sensitive and committed to all the subjects that hurt or shake up the world".

At 64, Tavernier has a young man's anger and enthusiasm. Anger led him to make L.627 "because they make a law and then they don't care if it's applied". The film is named after the French law on the treatment of drug-users, and is widely considered the truest film about the French police. As he gets older, Tavernier says, his films take on a new urgency. After 32 feature films and documentaries in as many years, he still makes "every film as if it were my first one".

Tavernier named his production company in north-east Paris Little Bear, after the Silver Bear award that his first film, The Clockmaker (1973) won at the Berlin Film Festival. Based on a novel by Georges Simenon, The Clockmaker is the haunting story of a father's transformation when his son is accused of murder.

Teddy bears are scattered throughout the Little Bear office. The big pink one in the conference room is a prop from Holy Lola. Geraldine (Isabelle Carré) clung to it on the back of a motor-scooter as Pierre (Jacques Gamblin) drove through the traffic of Phnom Penh.

Holy Lola is the story of a French couple's quest to adopt a child in Cambodia. You'd have to be heartless not to be moved by the scene where Carré and Gamblin finally meet Lola, after weeks of fighting mosquitoes, tropical rain and corrupt bureaucrats.

"For me it was the crucial shot in the film," Tavernier says. "We rehearsed it with a fake baby. Then we went to shoot it. In the first take, Lola held out her arms to be picked up. Isabelle Carré was so astonished that she started crying.

"She really cried. Jacques was taken by surprise. I have 25 seconds that were not written in the script. For all the people who shot it, that scene was very emotional."

Tavernier wanted to make a film about desire. "Desire is not necessarily about sexuality; it can also be to have a child," he explains. Carré plays the sterile young wife of a country doctor.

"Sometimes her desire to have a baby is so violent that she is ready to ignore the context," Tavernier says. "She has suffered a lot by the fact she is sterile, has been humiliated, feels diminished by it."

For years after you see a Tavernier film, a blurry impression, an indescribable feeling, lingers. It may be the the bubbly daughter who disrupts the pastoral calm of her elderly father's home in 1984's A Sunday in the Country (which won the best director award in Cannes), remembered as a gauzy 1912 dress, dappled sunlight and Fauré's music. Or the ageing, alcohol- and drug-addicted black American jazz saxophonist in 'Round Midnight (which won an Oscar in 1986) in a blue haze of Paris bars and stairwells. Or the desolation of Life and Nothing But (1989) and Captain Conan (1996), Tavernier's two finely focused narratives of the end of the first World War.

"I feel I have have succeeded when someone tells me the character is alive," Tavernier says. "In the films I like, I remember the atmosphere, the emotion, of the film more than the plot elements."

Hollywood junk films have destroyed the attention span of many film-goers, and by comparison, French films can seem long and slow. Tavernier refuses to give in to what he calls the tyranny of plot.

"It's not a question of slow or fast," he insists. "I want to give the impression that the story is written by the characters. I'm against using a plot device to solve an emotional problem.

"For instance, a coincidence - somebody happened to be listening at the door. Or suddenly two characters meet, and one of them should not have been there. It's fine for comedies or Agatha Christie. When you make a film that deals with human feelings, you must have a story, a construction, but you must not be the prisoner of a plot."

The directors he admires - John Ford, Kurosawa, Michael Powell, Ingmar Bergman - used very little plot, Tavernier says.

"A lot of books these days are based on plot," he says. "Sometimes in the plot I have a problem finding the characters. The characters can be flat and one- dimensional."

It is impossible to categorise Tavernier as a maker of period films, or of police films, or of social commentary, though he has done all of these. The common thread, he says, is that "most of my films are about people who are trying to change things around them. Sometimes they make mistakes, but they are passionate".

"They are discovering in the course of their fight," he adds. "They are not the same at the end of the film as at the beginning. Pierre and Geraldine [in Holy Lola] will not only have a baby, they will have learned about Cambodia, about a different way of thinking, about a different way of surviving.

"I am close to the foot-soldier, to the people who are in the trenches. I am not with the generals. I always quote a line from Kipling: 'Tell me the story of the foot-soldiers; I will tell you the story of every war.' "

Several times, Tavernier says, his films have changed things. Holy Lola has provoked a re-examination of French adoption laws. Henceforth, French embassies in countries such as Cambodia will have an official assigned to help couples seeking to adopt.

A series on landmines overseen by Tavernier resulted in a ban on the production of landmines in France. He is especially known for his commitment to the cause of the poor and immigrants. His documentary, Stories of Broken Lives (2001), about the double penalty - a prison term followed by expulsion - inflicted on immigrants convicted of crimes in France led interior minister Nicolas Sarkozy to change the law.

"That was before he did what he just did," Tavernier laughs bitterly, alluding to Sarkozy's decision to deport all foreigners convicted of participating in the recent riots.

The Other Side of the Tracks (1998), a documentary Tavernier made with his son, Nils, in the Paris suburb of Montreuil seven years ago, turned out to be prophetic.

"People came up to me in the subway and the street and thanked me for making it," he says. "They said: 'The TV cameras only come when we burn cars. No one ever talks to us.' The film ends with a young woman, Melanie, saying: 'Now that the film is finished, what is going to happen?' "

Tavernier repeats in a voiceover: "Yes, Melanie, now that the film is finished, what are we going to do?" The socialist government of the time spent millions of francs to improve conditions in Montreuil, but Tavernier is disillusioned with government policies towards the immigrant banlieues.

"People from the government, the ministers, don't care," he says. "They do not know the reality. A lot of people are like the French generals in the first World War who never went to the trenches. When they were told there was gas, they said it was an invention of the soldiers not to fight. It took three months for it to be believed by the doctors and generals."

For Tavernier, film-making is a family business. His ex-wife, Colo O'Hagan, who is Irish, wrote many of his screen-plays. His daughter, Tiffany, a novelist, co-wrote Holy Lola and It All Starts Today (1999), about a schoolteacher in impoverished northern France. His son, Nils, acted in L.627, went on to direct an acclaimed documentary about dancers at the Paris Opera, and is now directing his first feature film.

"I work with them not because they are family but because they are talented," Tavernier says.

As part of the Martell Cognac French Film Festival, which runs at the Irish Film Institute (IFI), Dublin, until Dec 1, Bertrand Tavernier will participate in a panel discussion on French cinema following the 3pm screening of L'Esquive on Sun at the IFI. He will also be present at the screening of Holy Lola at 6.30pm on Mon. After the screening, Henri Texier, who wrote and performed the score for Holy Lola, will give a concert. Tickets available from IFI box office (01-6793477) or Ticketmaster (0818-719300)