Led by Human Rights Watch, the organizations urge Libyan authorities to uphold its international legal obligations and promptly surrender the son of former president Muammar Gaddafi to ICC. Saif al-Islam Gaddafi, who was reportedly apprehended on Saturday in southern Libya, is subject to an ICC arrest warrant for crimes against humanity in an investigation authorized by United Nations Security Council Resolution 1970.

The resolution requires cooperation of Libyan authorities with any ICC investigation into serious crimes committed in Libya, including the surrender of ICC suspects. He is reportedly being held in the town of Zintan.

“The authorities will send an important message that there’s a new era in Libya, marked by the rule of law, by treating Saif al-Islam humanely and surrendering him to the ICC. His fair prosecution at the ICC will afford Libyans a chance to see justice served in a trial that the international community stands behind,” says Richard Dicker -international justice director at Human Rights Watch. “

There are several cases recent cases of mistreatment in detention the towns of Tripoli and Misrata, as well as apparent summary executions of suspected Gaddafi supporters by anti-Gaddafi fighters. The apparent killings in custody of Muammar Gaddafi and his son Muatassim Gaddafi on October 20 are particular cause for concern about Saif al-Islam’s treatment.

On March 3, 2011, ICC opened an investigation into serious crimes committed in Libya since February 15. The UN Security Council had referred the situation there to the ICC in Resolution 1970 on February 26. On June 27, ICC judges authorized three arrest warrants for Muammar Gaddafi, his son Saif al-Islam Gaddafi, and Libya’s intelligence chief, Abdullah Sanussi, who is reportedly still at large.

The three were wanted on charges of crimes against humanity for their roles in attacks on civilians, including peaceful demonstrators. These attacks were committed in Tripoli, Benghazi, Misrata and other locations in Libya. Consistent with Resolution 1970, the ICC warrants apply only to events in Libya beginning on February 15. Fair domestic trials for crimes committed before that date will thus be vital to ensuring redress for victims and respect for the rule of law in the country, Human Rights Watch said.

Surrendering Saif al-Islam Gaddafi to the ICC would not prevent the new Libyan authorities from preparing their own cases against him and others concerning events since February 15 or before.

Security Council Resolution 1970 requires the Libyan authorities to cooperate fully with the ICC. This includes surrendering him to the court. Should the Libyan authorities wish to try Saif al-Islam Gaddafi domestically for crimes in ICC’s arrest warrant, they can challenge – through a legal submission – the court's jurisdiction over the case.

The Libyan authorities will have to show that they are genuinely able and willing to prosecute the case in fair and credible proceedings. Demonstrating an ability to fairly prosecute Saif al-Islam Gaddafi would likely require swift and substantial reform of the judicial system.

For ICC to find that the case is inadmissible, and that it must be returned to Libya for prosecution, the Libyan proceedings must encompass both the person and the conduct that are the subject of the case before ICC.

Ultimately, it is up to ICC judges to determine whether any national proceedings exist that would trump the court's ability to hear this case. Because the ICC is a judicial institution, its proceedings must run their independent course.