IT is a deep assumption in this country that the police force exists to uphold the law firmly and fairly, to protect and reassure, and to bring criminals to justice.

The occasional story of police corruption or violence is greeted with horror--a reaction which, in itself, expresses the high standards we expect.

But, in some countries, police are abusers of human rights, rather than harbingers of community peace.

In Bosnia, the UN estimates that 70% of human rights violations during the war there were committed by the police force.

Although slashed and scarred by ongoing hostilities, awash with weapons and littered with mines, the country is now trying to reform its policing.

Operating under a UN banner is the International Police Task Force, bringing together officers from 44 countries to propel the country towards democratic, dignified and decent policing.

Hampshire Constabulary, like other forces across the country, commits a handful of officers to this programme each year. Right now, there's one in Bosnia and another in Kosovo.

But as Chief Constable, Paul Kernaghan, says, hardly anyone knows they are there.

"These contingents are not so much a forgotten commitment, as an unknown commitment."

Keith Huelin and Martin Badger, two Hampshire officers, have just returned.

Having passed a rigorous selection process and induction course, the two long-serving officers faced an almost imponderable task.

Themselves unarmed, they would take up managerial positions to supervise a multi-ethnic force whose officers, only five years ago, faced one another over gun barrels.

They would have no front-line policing powers, but by shadowing local officers would persuade them to interface impartially and transparently with the general public.

So, why did they decide to put themselves the firing line?

Martin (44), a Ringwood PC, has been in the force for 18 years. A committed family man with two children and five grandchildren, he simply suspected he was becoming stale.

"I just wanted to do something different," he says.

Keith (38), a Portsmouth DC, takes an eager slurp from a double espresso--nothing tastes strong enough after Croat coffee--and agrees with his colleague.

"I was looking for something different. Otherwise you just get so introverted, you don't know what's going on outside in the real world."

Having landed in Sarajevo and recovered from the shock of their new surroundings--the shelled buildings, still inhabited, and the gnarled infrastructure, still used--they separated.

Keith travelled north to a small town called Orasje, on the Croatian border.

Despite being "just a DC", he rose to the top at the IPTF station.

"It was part of my job to encourage people to regard the police as their police, instead of the state police.

"We were there to help the local police deal with everybody as an equal, instead of on the grounds of ethnicity.

"In my area, there were Bosniaks, Croats and Serbs. The demography of the local police must reflect this diverse community, so we were there to integrate people."

But, with each breath, he betrays a lurking shell shock.

"Everybody is armed out there," he says wearily. "Everybody, even children, carries explosives and grenades."

Having worked with a landmine clearance team, he says he became totally reckless about stepping on one--he was totally desensitised to the risk.

"UN intervention meant that the war came to an unnatural end--there was never a winner or a loser. The fighting is over but the war carries on. They are just waiting for the international organisations to leave."

He gives the impression that while people in Bosnia listen to what the police say, their compliance springs from fear, not respect.

Martin was 100km away in Tuzla where he took up a pivotal role as regional human rights investigator.

Patting his belly, he says that part of the trouble was the good food.

"Ah, yes, that lovely home-cooking--all that steak and those fresh vegetables," he sighs, in a reverie of remembrance.

But, like Keith, he also seems bruised by the experience.

"I was overseeing some of the worst areas, where there had been massacres. You get used to seeing mass war graves and dealing with police violence.

"There's also a lot of human trafficking--women forced into prostitution.

"I felt frustrated that we weren't able to help these people. There is such a lack of funding for police and so much red tape that you have to cut through it with a chainsaw.

"My major project was encouraging people to give up their weapons and, just as I was about to leave, I really started to see some results."

They describe their cultural wrangles--domestic violence, for one. In Bosnia, what goes on behind closed doors is simply not regarded as a policing matter.

And, although the police force is numerically strong, there is no "beat-bobby" culture.

Officers tour around in car-loads of six or more, leaving the whiff of siege mentality in their wake.

So, if there were disappointments to their experiences, how does it feel to be home again?

"Well, it's back to being at minion level now. But at least we can look back on what was demanding and adventurous," says Martin.

"Yeah," adds Keith. "We have much more of an idea of what we can achieve as individuals--much more."

As the chief constable has made clear, Hampshire is another beneficiary of this project.

"If we can disrupt a criminal conspiracy in Bosnia, we can prevent criminal activity and victimisation anywhere," he said.

* The landmine clearance team in which DC Keith Huelin worked desperately needs a four-wheel-drive vehicle to reach remote mountain villages--it has to be in reasonable working order and it has to be free! If you can help, please phone him at Fratton police station --08450-454545.