Roberto Ricci's first mission as a United Nations human rights investigator could also have been his last.

The Italian lawyer was sent to Rwanda in September 1994, having been given just ten days to prepare himself to investigate what turned out to be the genocide of an estimated 800,000 people.

“The mission there was to monitor the human rights situation and investigate what had happened,” he said. “At that time, human rights work in the field was still relatively new, although there had been missions in El Salvador and Guatemala. This was completely different.”

With some guidance - although not very much - he had to find his bearings in a situation that today would be considered far too dangerous: no satellite phone, no mobile phone, radios that worked only occasionally in the mountainous terrain and highly unstable security.

But it was not the practical difficulties he faced that threatened to overwhelm him; it was the enormity of the crime and a subsequent sense of helplessness, of the inability of good to triumph over evil.

“It is something that should never happen, should never have happened,” he said. “It was very hard for all of us, particularly because genocide - genocide is often spoken about, but very few people have experienced what it means.”

His job in Rwanda - and later on other missions - is to talk to survivors and witnesses to try to construct as accurately as possible what had happened. It is a job that requires a great deal of emotional awareness as well as practical knowledge of everything from international law to how to use a GPS to map the sites where bodies were found.

Investigators need an understanding of basic psychology so they can evaluate how closely they can question traumatised people without making things worse for them. “You also need some kind of understanding of anthropology so you can understand the social reality in which actions occur, and you need to be able to adapt to that,” Mr Ricci said.

Without that ability, an investigator might, for example, ask someone to estimate a distance in kilometres even though they only measure journeys by how long it takes to get somewhere.

In Rwanda, Mr Ricci and his colleagues had been there for almost six months before malaria forced him to stay at home for a while. It was the first occasion he had enough time to go for a walk in his own garden - where he found two skeletons.

“On another occasion we stayed at a beautiful hotel. I went out to stretch my legs on the beach of the lake and the first thing I saw was a leg sticking out of the sand. I went to places where there was no septic tank that did not have bodies floating in it.”

After 13 months, he realised that he could not keep going. A human rights investigator needs a commitment to justice and a capacity for empathy, but must also be able to keep his or her distance. “You are observing and you are reporting. You are also judging the system. You cannot not have an opinion but you have to keep that separate from what you are reporting.

“I had to leave because I lost my objectivity and became too involved. It starts making you doubt what you are doing, about whether it has any impact or not, and you start to resent the perpetrators not as individuals but as a group - in other words, not the single person who killed but all the military.”

Mr Ricci returned to Italy for a time, wrote an article that helped him to regain his perspective and then went back into the field. Since 1996 he has worked in more than 30 countries, including Croatia, Afghanistan and the Democratic Republic of Congo.

Does he feel that he is making a difference? “That's not an easy question to answer,” he said.

“The short answer is yes. I believe that this work has to be done. Human rights investigation is for justice: criminal justice, moral justice, the right for people to know and for their stories to be told.

“People need to come to terms with their own history. Perhaps if a country is not in a position to remember its own history at the moment, then this will help them.”

What it takes

Qualifications: There is no formal, set path into human rights investigation. The usual starting point is a postgraduate degree in international human rights and humanitarian law. Investigations also draw on experts who are qualified in relevant areas such as forensic anthropology or science.

Training: At least a basic field knowledge of international law, anthropology and psychology. Many begin in human rights campaigning and advocacy. Linguistic ability is also valuable.

Attributes: Investigators are part lawyer, part detective, part academic, part scientist. They need a commitment to justice; an understanding of psychology and how people react to trauma; the ability to maintain a dispassionate distance from the task; emotional resilience; strong stomach.

Earnings: Entry level roles at NGOs start at about $35,000 (£23,000) while senior UN investigators can earn up to $110,000-115,000 in the field.

Working life: Investigators could find themselves in the world's current or recent trouble spots. Life can be dangerous.

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