Defense lawyers have asked judges to rule on how much evidence they need to present to prove Dominic Ongwen is not responsible for the crimes he has been charged with at the International Criminal Court (ICC).

The application relates to the defense having stated they intended to present Trial Chamber IX with reasons why Ongwen should not be held responsible for the 70 counts of war crimes and crimes against humanity the prosecution has charged him with.

Article 31 of the Rome Statute, the ICC’s founding law, sets out the grounds an accused person can argue to show they were not responsible for the crimes they have been charged with. In August 2016, Ongwen’s lawyers notified the court that in Ongwen’s defense they would be using two provisions under Article 31: mental disease or defect and duress. They also gave notice of an alibi Ongwen had, but alibis come under different legal provisions at the ICC.

This is the first time since the ICC began work in 2002 that Article 31 has been invoked by a defense team. To date, no trial chamber has had to rule on who is responsible for presenting evidence in relation to the provisions of Article 31. In addition, no trial chamber has ruled on the level of evidence needed to prove the grounds of defense under Article 31.

These are the issues Ongwen’s lead lawyer, Krispus Ayena Odongo, has raised in a January 28 application. Odongo has asked Trial Chamber IX to determine who has the burden of proving an accused person is not responsible for the crimes they have been charged and what standard of proof they need to satisfy.

Odongo has argued the defense is only required to show there is evidence Ongwen was not responsible for the crimes he is alleged to have had a role in as a commander of the Lord’s Resistance Army (LRA). He has also argued once the defense has done so, the prosecution is obliged to lay out evidence that shows beyond a reasonable doubt Ongwen was capable or able to commit the crimes he has been charged with.

“If the Prosecutor cannot do this, the defences under Article 31(1)(a) and (d) succeed and the Accused must be acquitted,” said Odongo.

A defense of mental disease or defect is covered under Article 31(1)(a) of the Rome Statute. A duress defense is provided for under Article 31(1)(d).

On Thursday, the prosecution filed a response to the defense application. The prosecution argued that the defense is wrong in framing Article 31 in terms of “burdens” on the parties. They said that the trial chamber is independently responsible for deciding whether grounds to exclude criminal liability apply to Ongwen’s case. The prosecution said they or the defense may present the chamber with evidence on the issue, but the chamber could also decide to call its own evidence.

“The Prosecution of course accepts and embraces its obligation under Article 66 to prove the Accused’s guilt beyond reasonable doubt. However, that does not settle the issue raised in the Defence Request.

“Any ground for excluding criminal responsibility under Article 31 must be based upon a substantial evidentiary basis in the record of the case. The Statute does not say who must present such evidence, although common sense suggests that the Defence will often both have an interest in doing so and be in a particularly good position to do so,” said Fatou Bensouda, the ICC Prosecutor.

On Thursday, lawyers representing one group of victims registered to participate in the trial of Ongwen also filed their response. This group of lawyers, known as the Common Legal Representative for Victims (CLRV), has argued Trial Chamber IX should dismiss the defense application. However, the CLRV said that if the chamber chooses not to dismiss the application, then the judges should rule the defense is obliged to present evidence to show Ongwen was not responsible for the crimes he has been charged with.

The CLRV asked judges to dismiss the defense application because it is time-barred. The CLRV argued that the defense should have asked the chamber to make a ruling on the issue of burden and standard of proof in August 2016, when they gave notice they were going to invoke Article 31.

“The CLRV underlines that the Defence did not exert due diligence in raising its Request at the earliest available opportunity considering that more than two years and half have passed since its notification. Indeed, as is self-evident, the Defence knew about its own intention to raise such defences at the time it informed the Chamber, the Prosecution and the Legal Representatives of Victims,” said Paolina Massidda, the lead lawyer of the CLRV.

In August 2016, the defense also gave notice that they would be presenting an alibi defense in relation to one set of charges against Ongwen. The alibi the defense said they would present is in relation to an October 10, 2003 attack on the Pajule camp for internally displaced people. Article 31 does not provide for an alibi defense, but it is covered under Rule 79 of the ICC Rules of Procedure and Evidence.

On Monday, the defense filed a request to reply to the responses of the prosecution and the CLRV. The chamber may grant or deny that request. Once that request has been dealt with, the chamber will then make a decision on the defense application. There is no deadline the chamber must meet to do so.