Madeleine Rees, the UN High Commissioner for Human Rights in Bosnia, has broken ranks to demand that UN officials, international peacekeepers and police who are involved in sex crimes be brought to justice in their home countries.
The British lawyer has also launched an outspoken attack on her former boss, Jacques Paul Klein – former head of the UN Mission in Bosnia – of not taking UN complicity in the country’s burgeoning sex trade seriously enough.
In recent years there has been a massive increase in the trafficking of women in Bosnia, including girls as young as 12. The women are taken from their homes in eastern Europe by organised criminal gangs and brought to Bosnia, where they are forced into prostitution.
The trade in these so-called ‘sex slaves’ hardly existed until the mid-1990s. It was fuelled by the arrival of tens of thousands of predominantly male UN personnel in the wake of the signing of the Dayton Peace Accord by Bosnia, Croatia and Yugoslavia in 1995.
Rees said: "Visiting brothels where women have been gang-raped into submission, into slavery, is not part of the UN’s mandate.
"Without an enforceable code of conduct, immunity often means impunity. We should look at ways of waiving that immunity.
"I would be very happy to see the possibility of prosecutions for rape or assault in the UK. There is no question this should happen."
Rees, who has served in Bosnia since 1998, said she had encountered stiff opposition from western officials in her attempts to tackle the trafficking of women.
"They don’t want to know about it," she said.
"There is this whole ‘boys will be boys’ attitude about men visiting brothels. There’s a culture inside the UN where you can’t criticise it. That goes all the way to the top."
Referring to Klein, she added: "He doesn’t take this issue at all seriously."
Last year, Rees testified in support of Kathryn Bolkovac, a UN police officer who was sacked for exposing the sexual abuse of women and children in Bosnia by her colleagues.
Bolkovac’s former employer DynCorp, an American security firm which supplied staff to the UN, was forced to pay £110,000 in compensation.
The chairman of the British employment tribunal which heard the case described DynCorp as "callous, spiteful and vindictive".
Bolkovac had revealed UN peacekeepers went to nightclubs where young girls were forced to dance naked and have sex with customers, and that UN personnel and international aid workers were linked to prostitution rings in the Balkans. At the time, Rees described it as "the biggest cover-up I have ever seen", adding that she believed 30 per cent of those visiting Bosnia’s brothels were UN personnel, peacekeepers or aid workers.
DynCorp insists it has the highest ethical standards of business "and encourages employees to speak openly."
However, Rees said the private defence contractors, whose British office is based in Salisbury, should be banned from the country.
"DynCorp… should not be allowed anywhere near Bosnia," she said.
In January, a 500-strong European Union police force replaced the UN’s 1,800 member multinational International Police Task Force (IPTF).
Dedicated anti-trafficking teams were formed and assigned to raid nightclubs across Bosnia suspected of operating forced prostitution rackets.
Rees said the counter-trafficking efforts had mostly been a failure. "They were basically for show and completely amateurish," she said.
Referring to the EU police force, Rees added: "They are still very much on probation. These men must understand that going into brothels is illegal in Bosnia. The sex is not consensual if the woman is a 13-year-old girl trafficked from Moldova."
Although there have been many cases of police officers being sent home in disgrace for their involvement in the sex trade, the UN can only remove them from service and is powerless to prosecute them. It is up to member countries to take any further action.
Rees said: "People will say the UN is not practising what it preaches. It is double standards, and it looks like western imperialism. Brothel raids find UN police inside, and then no one is prosecuted. The UK is prosecuting no one.
"If you send people home, countries get wild. But if you don’t enforce the rules, you can’t serve in the United Nations."
Human Rights Watch is equally downbeat in its assessment.
A spokesman for the organisation said: "Foreign nationals serving in Bosnia enjoy almost complete immunity. It was assumed countries would prosecute and discipline their citizens upon their return home from for crimes committed in Bosnia and Herzegovina. This has rarely happened in practice."
Soldiers from S-FOR, or Stabilisation Force, Bosnia’s 18,000 strong Nato-led peacekeeping force, were granted "immunity from personal arrest or detention" by the November 1995 Dayton Treaty which authorised their deployment.
S-FOR troops are banned from attending brothels but Rees said the marketing strategy of suspected new brothels opening near S-FOR bases makes it clear who they are catering for.
"Outside the Russians’ base, there is a brothel called Odessa," she explained. By the Americans’, its Texas or Philadelphia. There’s even an El Cid near the Spanish base. While there are foreign troops in Bosnia, there will be always demand for trafficked women."
Last night, Jan Oskar Solnes, spokesman for the European Union Police Mission in Bosnia and Herzegovina, said: "Its correct we have diplomatic immunity, but I imagine any incident [of sexual misconduct] would be a personal rather than professional matter.
"We have a zero tolerance approach to this issue and anyone involved will be removed from the mission."
Kirsten Haupt, spokeswoman for the United Nations Liaison Office (UNLO) in Bosnia, dismissed Rees’s claim that Jacques Paul Klein had not taken the illegal sex trade seriously.
She said: " All cases have been thoroughly investigated. We have sent a number of officers home. There is absolutely no toleration of a ‘boys will be boys’ attitude here."
Klein left Bosnia on February 1 and could not be contacted.
A spokesman for DynCorp said: "We do not make it a practice to comment on opinions.
"However, we are familiar with previous public statements Ms Rees has made about involuntary servitude and DynCorp continues to share her concerns for women held against their will in Bosnia, just as we condemn all human rights abuses anywhere in the world."