Sudanese lawyer and member of parliament Salih Mahmoud Osman is seeking to change Sudan's legislation to bring the country's state security forces within the rule of law.
However, he faces an uphill struggle against an administration determined to protect its servicemen from prosecution for crimes including murder, torture and rape.
Osman says: "We are talking about a situation where there is a pressure and an atmosphere of impunity. All of the crimes that have occurred in Darfur are of a serious nature: crimes against humanity and war crimes and, as far as I am concerned, acts of genocide."
Osman hails from Sudan's Darfur region, which has made headlines in recent months for the scale of the brutality. Thousands of civilians have been murdered, raped, tortured or displaced since the start of a 2003 revolt by rebels from Darfur's ethnic African population.
Sudan's government is alleged to have responded by unleashing militias against villagers and, even as it resists pressure to allow UN peacekeepers to enter the region, it has launched a new military offensive against them.
Osman and other lawyers have sought to bring perpetrators of these crimes to justice by filing cases against them. But, as he explains, under the state-of-emergency laws, state security forces are almost immune from prosecution.
"The court of law makes justice almost impossible because lawyers have to obtain permission from the courts to take court action against members of the military," he says. "Also, under [Sudan's interpretation of] sharia law, to bring a case of rape requires a minimum of four male witnesses."
Osman adds that lawyers are also intimidated when they try and take cases to court and are frequently arrested and detained.
Following his own release from jail in 2004 - he was held incommunicado for seven months without trial in Kober prison - Osman also joined the human rights NGO Sudan Organisation Against Torture (SOAT), which takes cases on behalf of victims of torture and repression.
Meanwhile, in his role as a parliamentary member of opposition political party the National Democratic Alliance, Osman is trying to abolish the national security law under which permission is required for security forces to be taken to court during a state of emergency.
He is also trying to introduce laws expressly prohibiting genocide and crimes against humanity and to change the law on rape to make it easier to bring cases to court.
"We're trying to ensure the rule of law," he says. "But we need the rest of the world to keep up the pressure on our government."
For more information on SOAT, see www.soatsudan.org.