This Tuesday, lawyers for Dominic Ongwen will tell the International Criminal Court (ICC) that Ongwen cannot be held responsible for the crimes he has been charged with because he suffered a mental illness or defect, he acted under duress, and, for some of the charges, he has an alibi.

Ongwen’s lawyers will make their opening statement this week because they chose to do so when the defense phase of the trial begins rather than when the trial opened in December 2016. They had this option under the initial orders on how the trial will proceed that Single Judge Bertram Schmitt issued in July 2016.

The grounds of defense Ongwen’s lawyers intend to present are provided for in Article 31 of the ICC’s founding law, the Rome Statute. They already gave notice on August 9, 2016 that they would argue duress and an alibi as grounds of defense. They also gave notice they intended to argue mental illness or defect as a defense, but that notice is not public. The defense phase of the trial begins this week after the prosecution concluded its case in April this year and the victims’ presented their case in May.

Ongwen has been charged with 70 counts of war crimes and crimes against humanity for crimes he is alleged to have committed as a commander of the Ugandan rebel group, the Lord’s Resistance Army (LRA). He is alleged to have committed these crimes between July 1, 2002 and December 31, 2005.

The charges against Ongwen include his alleged role in attacks on four former camps for internally displaced people (IDP) in northern Uganda and sex and gender-based crimes.

At the start of the trial in December 2016, Ongwen’s lawyers requested it be suspended because they said Ongwen was not mentally fit to stand trial. They made the application a day before the trial began on December 6, 2016 and they based it on the assessment of two psychiatrists they hired. Ongwen’s lawyers only presented the court with the report of those psychiatrists after the judges ruled on their application on December 6, 2016.

On that day, Trial Chamber IX ruled that Ongwen was mentally fit to understand the charges against him and take a plea. They, however, later appointed a psychiatrist, Joop. T. V. M. de Jong, to determine what Ongwen’s mental health needs were.

The defense’s attempt to get the trial suspended on grounds of mental health brought to the forefront this line of defense that Ongwen’s lawyers intended to pursue. This also prompted the prosecution to call three mental health experts that they had not, at the start of the trial, planned to call.

Throughout the testimony of prosecution witnesses, Ongwen’s lawyers have questioned them about the violent ways the LRA initiated its new abductees. Ongwen’s lawyers have also questioned some witnesses about what they knew of the deaths of two former deputy LRA leaders, Otti Lagony and Vincent Otti. They have argued in filings that the details of Vincent Otti’s death is a key element of their duress defense.

The other defense Ongwen’s lawyers intend to present is that he was not present during the attack on the Pajule IDP camp in October 2003. They have questioned several prosecution witnesses about this. For those witnesses who testified they saw Ongwen during the Pajule attack, his lawyers have pressed them hard on the details. An example of this is during the testimony of Witness P-249.

Ongwen’s lawyers have indicated they may call as many as 66 witnesses to testify. By the close of their case in April this year, the prosecution had called 69 witnesses.

According to a July 5 decision on protective measures for defense witnesses, some of the witnesses the defense will call are three children of LRA leader Joseph Kony; a former “wife” of Kony; former LRA fighters who are now in Uganda’s military; former members of a government-backed militia used to protect the IDP camps, the Local Defense Unit; and psychiatrists Emilio Ovuga and Dickens Akena.

This number may change. It is possible the defense may call other expert witnesses, if the trial chamber allows it.

In a June 4 filing, the defense had asked Trial Chamber IX to allow them to add experts they want to call but whose appearance they had yet to confirm. On June 21, Single Judge Bertram Schmitt declined to grant the request before the defense had secured the commitment of the experts to appear in court. The judge said the defense could file another request once the experts agreed to testify and provided the materials the defense needed.

The people the defense indicated they are working to call are an expert in audio recordings; one on the formation of IDP camps in northern Uganda; and a political scientist who has studied the LRA and its “cosmological and military space.” Other experts the defense would like to call are someone who has researched sex and gender-based crimes; an expert on child-soldiers who is also a former child-soldier; an expert on military structure; and one on direction finding.

Ongwen made his first appearance before the ICC in January 2015, almost 10 years after the court issued an arrest warrant for him. Ongwen is believed to have initially surrendered himself to a rebel group in the Central African Republic who then handed him over to a contingent of the African Union peacekeeping force. AU peacekeepers then handed him over to Central Africa Republic judicial authorities who then informed Ongwen of the July 2005 arrest warrant and processed him on January 16, 2015 for handover to the ICC.

The arrest warrant issued against Ongwen originally applied to four other LRA commanders: Kony, Otti, Raska Lukwiya, and Okot Odiambo. The ICC has terminated the cases against Lukwiya and Odiambo once their deaths were confirmed. Otti is widely believed to have been killed on the orders of Kony sometime in 2007 but the court is yet to formally declare him dead. Kony remains at large.

Ongwen’s lead lawyer is Krispus Ayena Odongo who at one time served as legal advisor to the LRA during peace talks that were held between 2006 and 2008. Odongo’s co-counsel are Charles Achaleke Taku and Beth Lyons. Taku is also a defense lawyer in another case before the ICC. Lyons has served as defense counsel before the International Criminal Tribunal for Rwanda. They are assisted by Thomas Obhof, Abigail Bridgman, Michael Rowse, Tibor Bajnovic, and Roy Titus Ayena.