For a man who says he’s committed to films he can believe in, it’s odd to find Danny Glover in a movie called Death in Timbuktu that was shot in Africa and spoofs spaghetti westerns. Until you realise that this is a film within a film, a part of the recently released Bamako by the Mauritanian writer-director Abderrahmane Sissako.

“There’s an exciting film-making scene in Africa,” says the star of the Lethal Weapon films, and I’m just doing my bit to help.”

For Glover, “doing my bit” means more than providing a cameo. His company helped to produce the film, which envisions a people’s court in the capital of Mali that puts the IMF and the World Bank on trial for Africa’s debt crisis. “I have been going to Africa for more than 30 years. I studied African political economy as a young man and Bamako is the kind of project one dreams about,” he says. For Glover, a Hollywood film such as Black Diamond is an oversimplification of events. “It reduces the whole political back story to the issue of conflict diamonds. Don’t buy them and everything will be solved? It’s not that simple.”

And while he admires Forest Whitaker’s Oscar-winning portrayal of Idi Amin in The Last King of Scotland , he still wonders why it’s framed by a story “about a fictitious white doctor when Amin’s relationship with his photographer would have been more interesting”.

Glover is still best known as a Hollywood character actor, most recently seen in Dreamgirls. But the 60-year-old actor’s off-screen roles have included calling for the abolition of the death penalty, campaigning for the environment and working for human rights.

No wonder Amnesty International gave him a lifetime achievement award. But he has also been chided by the National Association for the Advancement of Coloured People (NAACP), to which his parents belonged when he was growing up in San Francisco, for playing a wife-beater and child-abuser in Steven Spielberg’s film The Color Purple .

Even so, the NAACP later honoured him with awards for playing Nelson Mandela on TV and the responsible cop and family man Roger Murtaugh in Lethal Weapon . “That’s as it should be,” Glover says. “If Purple hadn’t stimulated debate it would have meant something was wrong with the film. I don’t think that what I do should go unnoticed.”

Glover says he was politicised as a teenager visiting his grandparents in segregated Georgia. As a student he acted in the plays of the antiapartheid South African playwright Athol Fugard. “I realised that theatre could raise awareness,” he says. In 1976 he enrolled in drama school.

Hollywood took notice of him after his appearances in New York in the Fugard plays Master Harold and the Boys and The Blood Knot and appearances in several high-profile films led to auditioning for Lethal Weapon . Since then his career has been a mixture of Hollywood block-busters, indie films and issue-driven stories. His next three films, for example, are Poor Boy’s Game , a drama about a vengeance-seeking father, Honeydripper , a period musical drama by John Sayles, and Shooter , which stars Mark Wahlberg as an army sniper.

Isn’t a gun-toting entertainment such as Shooter at odds with Glover’s off-screen role as a protestor against guns? “Listen, Hollywood has been good to me. It’s allowed me to help my family over the years. Now I’ve got to think of my granddaughter’s future. People such as Morgan Freeman and myself are getting on and we still don’t have the same opportunities enjoyed by Jack Nicholson. So you’ve got to think long-term regarding your career."

So would he consider another Lethal Weapon then? “Oh man, those films said all they had to say, don’t you think? It’s better to keep looking forward.”

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