“Women have been talking about these issues for a long time,” he said. “I’m not the first person to take up this fight in this country, I’m just the first man, and that makes it a lot easier.”

“I come from these communities. I understand their patriarchal nature. I can challenge them,” he continued. “And because I am a man, the men in the community are more likely to listen to me.”

Women’s rights campaigners have welcomed Mr. Afzal into their sisterhood. Efua Dorkenoo, advocacy director on female genital mutilation for Equality Now, said male allies were “critical” for the success of gender equality campaigns, especially when rights abuses are cloaked in cultural terms.

“When men like Afzal speak up about violence against women, it has much more resonance in Asian and African communities,” she said. “When we women speak up, we are often dismissed as westernized and no longer speaking for the community.”

It was in 2004 that Mr. Afzal, a father of one daughter and three sons, had his own wake-up call when a group of women came to see him. One told of a girl who had burned herself to death to avoid a forced marriage. She had been 17, the same age his daughter is now. Another recounted the story of a woman who had been on the run from her family for more than eight years after refusing to marry a man she did not know. His visitors pressed Mr. Afzal to use his office to bring honor crimes and forced marriages out of the shadows and into the courtroom.

“I didn’t know this was happening in this country,” he said. But the stories shook him, and that same year he organized a conference in London to learn more. Shortly after, he sat down with the police to pull together a national database on honor crimes. “Before I knew it, we had dozens and dozens of cases,” he said.

TWO years later he successfully prosecuted the cousin and the brother of a young woman, Samaira Nazir, for her murder. Ms. Nazir had wanted to marry someone to whom her family objected, a desire for which she was stabbed 18 times in front of two infant nieces who were splattered with her blood. Her father was charged with arranging the stabbing, but he died before the trial. It was one of the first times an honor killing had drawn public attention in Britain.