The following  was first published as an op-ed in The Washington Post on Oct 23, 2010. The writer is the United Nations high commissioner for human rights.

Seth Walsh walked into the garden of his family's home in Tehachapi, Calif., last month and hanged himself. He was just 13. Before making the tragic decision to end his life, however, he had endured years of homophobic taunting and abuse from his peers at school and in his neighborhood. He is one of six teenage boys in the United States known to have committed suicide in September after suffering at the hands of homophobic bullies. 

In the past few weeks there has been a spate of attacks directed against people perceived to be gay, lesbian, bisexual or transgender. In New York on Oct. 3, three young men, believed to be gay, were kidnapped, taken to a vacant apartment in the Bronx and subjected to appalling torture and abuse. In Belgrade on Oct. 10, a group of protesters shouting abuse hurled Molotov cocktails and stun grenades into a peaceful gay pride parade, injuring 150 people. In South Africa on Sept. 25, a large-scale march in Soweto brought attention to the widespread rape of lesbians in the townships, assaults that perpetrators often try to justify as an attempt to "correct" the victims' sexuality. 

Homophobia, like racism and xenophobia, exists to varying degrees in all societies. Every day, in every country, individuals are persecuted, vilified or violently assaulted, even killed, because of their sexual orientation and gender identity. Covert or overt, homophobic violence causes enormous suffering that is often shrouded in silence and endured in isolation. 

It is time we all spoke up. While responsibility for hate crimes rests with the perpetrators, we all share a duty to counter intolerance and prejudice and demand that attackers be held to account. 

The first priority is to press for decriminalization of homosexuality worldwide. In more than 70 countries, individuals still face criminal sanctions on the basis of their sexual orientation. Such laws expose those concerned to the constant risk of arrest, detention and, in some cases, torture or even execution. They also perpetuate stigma and contribute to a climate of intolerance and violence.

But as important as decriminalization is, it is only a first step. We know from experience in those countries that have removed criminal sanctions that greater concerted efforts are needed to counter discrimination and homophobia, including legislative and educational initiatives. Here again, we all have roles to play, particularly those in positions of authority and influence, such as politicians, community leaders, teachers and journalists.

Sadly, those who should be exercising restraint or using their influence to promote tolerance too often do just the opposite, reinforcing popular prejudice. In Uganda, for example, where violence against people based on their sexual orientation is commonplace, and activists defending the rights of gay, lesbian, bisexual and transgender people face harassment and the threat of arrest, a newspaper published a front-page story on Oct. 2 "outing" 100 Ugandans it identified as gay or lesbian and printed their photographs alongside the headline "Hang Them."

We must recognize such "journalism" for what it is: incitement to hatred and violence.

Political leaders and those who aspire to public office have a particularly important duty to use their words wisely. The candidate for public office who, rather than appealing for tolerance, makes casual remarks denigrating people on the basis of their sexuality may do so in the belief that he or she is indulging in harmless populism -- but the effect is to legitimize homophobia.

Last month I spoke in Geneva as part of a panel discussion on decriminalizing homosexuality. The event was sponsored by a diverse group of 14 European, North American, South American and Asian countries. In a video message, Archbishop Emeritus Desmond Tutu lent his support and spoke with passion about the lessons of apartheid and the challenge of securing equal rights for all. "Whenever one group of human beings is treated as inferior to another, hatred and intolerance will triumph," he said. It should not take hundreds more deaths and beatings to convince us of this truth. It is up to all of us to demand equality for all our fellow human beings, regardless of their sexual orientation or gender identity.