With two Khmer Rouge leaders arrested this week, one brought to hospital and public hearings scheduled for a fourth later this month, victims say they are still unclear on complaint procedures or other means of involvement in proceedings.

The $56-million tribunal has taken years to form, and one of its mandates is to encourage victim participation. Victims can file against cadre who killed family members, even though those cadre have not been charged, said Hisham Mousar, a legal expert with the rights group Adhoc.

The law only provides for the arrest of "top leaders," such as the four already in custody, but complaints against lower cadre will still be important for these cases, as cadre will be called as witnesses in those trials.

"I wish to appeal to victims: do not pay attention to the top leaders," Hisham Mousar said. "Work to submit a complaint, and then wait for the courts, especially the co-investigating and co-prosecuting judges, to work to identify which Khmer Rouge leaders are involved with [the victims] of a case."

If a victim can identify a perpetrator of a Khmer Rouge crime, the judges can assess whether to call that perpetrator as a witness "to show who ordered [the crime] at that time, and also to call those who were ordered to questioning," he said. This will help "identify who was the leader responsible in each case."

The tribunal has made available on its Web site the rules by which victims can participate.

Victims can be called as a witness, or victims may "participate actively…either by filing complaints with the co-prosecutors [or] applying to be joined as civil parties to co-investigating judges or before the Trial Chamber," according to the tribunal.

A Victim's Unit will become the office to file to, but it has not yet been established. Until it is set up, complaints should be filed with the offices of the prosecutors or investigators. Both of these offices can be found at the headquarters of the Extraordinary Chambers in the Courts of Cambodia, the official name for the tribunal, outside Phnom Penh.

Prosecutors are responsible for all written complaints or information on crimes under the courts, according to the tribunal. These complaints can be filed by "any person, organization or other source who witnessed or was a victim" of Khmer Rouge crimes. Victim associations and lawyers can also file complaints to the prosecutor's office.

The complaints should include the identity of the victim, subject of complaint, summary of alleged crimes, potential witnesses, evidence in possession of the victim and a note on whether the victim is willing to be part of a civil party suit.

When the Victims Unit is established, it can help administratively with the complaint, according to the tribunal, but a complaint will not automatically lead to criminal prosecution.

According to tribunal regulations, civil complaints—different from criminal complaints—must meet certain criteria, including the suffering of harm by the ordering of a Khmer Rouge crime. The harm can be physical, material or psychological, including the deaths of family members who were victims of a Khmer Rouge crime.

Only cases under tribunal investigation are eligible for civil complaints.

More information can be found at the tribunal's victim Web page: http://www.eccc.gov.kh/english/victims_unit.aspx