During his questioning by prosecutors, Shou confirmed the authenticity of a war-time diary he kept in Vukovar.
He wrote about the evacuation of the Vukovar hospital on 20 November 1991 which came to a head with the massacre of over 250 wounded Croatians at the Ovcara farm outside the town.
In his notes, Shou criticised both the former Yugoslav People's Army (JNA) and the International Committee of the Red Cross (ICRC) over poor organisation and lack of control during the evacuation.
"There is no security, there are many Chetniks (armed Serb nationalists) in the hospital walking around and beating the wounded... there are many drunken officers but few soldiers to carry the wounded. There is neither control nor organisation," the Dane wrote in his diary, blaming the JNA and the ICRC for the situation.
Asked by prosecutor Marks Moor to explain why he held the ICRC accountable for the situation, the witness said that on 20 November 1991 ICRC representative Nicholas Borsinger had only criticised the JNA and argued with everybody, instead of making a list of the wounded or doing something else.
He confirmed that the JNA and the ICRC should be held responsible for a lack of ambulances, which was why seriously wounded persons were taken to buses.
Shou also wrote that the wounded and the hospital staff had been taken from the hospital before ECMM observers arrived at the spot.
The International Criminal Tribunal for the former Yugoslavia (ICTY) charges Mrksic, Radic and Sljivancanin, also known as the Vukovar Three, with crimes against humanity committed when 264 wounded Croatian civilians and soldiers were massacred at the Ovcara farm where they had been transported from the Vukovar hospital after the town fell into the hands of Serb rebels and the JNA.