SUOS Thy - ECCC

Background and Role

Suos Thy, a farmer,¹ joined the Khmer Rouge militia in 1971.² He was reassigned as a medic after being wounded in 1973,³ and began working at PJ prison (the central police prison) in late 1975 at the request of Hor, regiment chief in Division 703.⁴ In late 1975 or early 1976, PJ prison moved to Tuol Sleng,⁵ as did Thy.⁶ Duch acknowledged Thy’s role at S-21,⁷ describing his testimony as truthful.⁸ The Trial Chamber relied on Thy’s testimony in making findings about S-21’s structure and operations, who was detained there, and how they were treated and eventually killed.

PJ Prison

PJ Prison belonged to division 703.⁹ Nat was the chair first, and Huy was his deputy.¹⁰ Duch then replaced Nat.¹¹ Thy was responsible for preparing lists of detainees brought into PJ prison.¹² He recorded the detainee’s name, their parents’ names, and where they were from.¹³ He estimated there were less than 100 detainees, mostly factory workers and “the people of the 17th of April”.¹⁴ He said he didn’t know why people were detained at PJ prison.¹⁵ When PJ prison was closed, all the detainees were transferred to S-21.¹⁶

S-21 Command Structure

Duch was the chairman of S-21; everything had to be done through him.¹⁷ Duch would give instructions to his deputy Hor, who would relay them to Thy.¹⁸ When PJ prison transferred to S-21, Thy was transferred too. He was initially assigned to keep lists; write and record detainees’ biographies; and report on the daily number of incoming and outgoing detainees.¹⁹ In court, Thy confirmed he had prepared detainee lists and biographies.²⁰ Thy kept records of detainees’ statuses, such as whether they were sick, escaped, or died, and made a daily report.²¹ Every day at 7am, Thy gave Hor a list of incoming detainees. After Hor signed the list, Thy took it to Meng, the head of the interrogation unit.²² Peng was in charge of the lists of detainees at S-21.²³ Thy explained S-21 had three primary units: S-21A, which included the interrogation unit, and economics, photography and typing sections;²⁴ S-21B, which included the guards’ unit (including the Special Unit) and cadre cooks;²⁵ and S-21D, the rice fields unit or re-education unit later known as S-24.²⁶ Thy served in S-21B.²⁷ The medical unit was initially under S-21A, but after the original medics were arrested, new medics were placed under S-21B.²⁸ Thy concluded that the General Staff supervised S-21.²⁹ Staff members at S-21 feared their superiors would have them arrested or killed.³⁰ Even Hor was afraid of Duch.³¹ Thy claimed he did not like his work, but felt he had to continue or he would be arrested like other staff.³² In court, he expressed regret that detainees were killed.³³

Detainees

Detainees were brought to S-21 from all over Cambodia.³⁴ The Special Unit would bring in handcuffed and blindfolded detainees and Thy would record a brief biography including a detainee’s name, position, and where they were from.³⁵ Detainees would be stripped to their underwear and of their belongings,³⁶ photographed, and taken to their cells.³⁷ Thy would record where a detainee was held.³⁸ Detainees’ photographs were later attached to their biographies.³⁹ Typically, detainees were brought in small numbers, but towards late 1978 some groups were brought en masse.⁴⁰ Small groups would be brought in on foot, and larger groups by vehicle.⁴¹ Families were arrested together: wives with husbands and children with their parents.⁴² The children were not photographed, their biographies were not taken, and they were not registered in official lists.⁴³ About 100 Vietnamese civilians and fewer Vietnamese soldiers were detained;⁴⁴ their interrogation was supervised by Mam Nai, aka Chan.⁴⁵ Important detainees were placed in a special prison.⁴⁶ If one became ill, Duch was informed.⁴⁷ Thy was not involved when those detainees were smashed, but Hor would inform him so he could include them in reports.⁴⁸ About 100 S-21 staff were arrested on Duch’s orders; Hor gave Thy their names afterwards.⁴⁹ Once arrested, they were treated like other detainees and eventually killed.⁵⁰ All the medical staff were arrested and replaced with teenagers.⁵¹

Conditions of detention

Most detainees were malnourished and held in poorly ventilated rooms.⁵² Some starved or were tortured almost to death.⁵³ If a detainee died, the medical unit would report they had been ill.⁵⁴ When detainees died, Thy adjusted the detainee list.⁵⁵ There were lists of detainees to be smashed and whose blood was to be drawn.⁵⁶ Duch had to authorize any removal of a detainee from S-21,⁵⁷ and identified who should be smashed.⁵⁸ Duch gave Hor lists with annotations which Hor relayed to Thy.⁵⁹ Thy then registered the detainees’ room numbers and Hor assigned guards to remove them from their cells.⁶⁰ Thy confirmed detainees’ identities at the front gate.⁶¹ They were then taken away for execution, often by truck,⁶² usually around 4pm.⁶³ Children were separated from their parents and were all killed.⁶⁴ After executions, Thy verified the list of remaining detainees⁶⁵ and provided a list of smashed detainees.⁶⁶ Thy did not recall any detainee being released, though one escaped.⁶⁷ He did not recall any detainee remaining at S-21 longer than two months.⁶⁸ In late 1978 or early 1979, all detainees were taken away and killed except those who were allowed to work and those in the special prison.⁶⁹ The medical unit would request authorization from Hor to draw blood from detainees, and Hor would request authorization from Duch.⁷⁰ If it was authorized, Thy would tell the guards where the relevant detainees were held.⁷¹ Thy estimated about 20 detainees had their blood drawn,⁷² though the Chamber found more than 100 had been subjected to this treatment.⁷³ When a detainee’s blood was drawn, it was reported to Hor, who would include that detainee on the list to be smashed.⁷⁴

Departure from S-21

Thy, other staff, and detainees who worked at S-21 fled on 7 January 1979.⁷⁵ Thy claimed Vietnamese troops’ arrival was a surprise and there was no plan to destroy documents.⁷⁶ The Chamber noted his evidence in concluding some documents may have been lost when S-21 was abandoned.⁷⁷

Videos

Testimony
Date	Written record of proceedings	Transcript number
27 July 2009	E1/54	E1/54.1
28 July 2009	E1/55	E1/55.1

Relevant documents
Document title Khmer	Document title English	Document title French	Document D number	Document E3 number
កំណត់ហេតុនៃការស្តាប់ចម្លើយសាក្សីឈ្មោះ សួស ធី របស់សហ ចៅក្រមស៊ើបអង្កេត ចុះថ្ងៃទី១៨ តុលា ឆ្នាំ២០០៧	Written Record of Interview of SUOS Thy by OCIJ on 18 October 2007	Procès-verbal de l’audition du témoin SUOS Thy par le Bureau des co-juges d’instruction le 18 octobre 2007	D22/9	E3/444
ឧបសម្ព័ន្ធ៨៖ បទសម្ភាសន៍ជាមួយ សួស ធី	Interview with Suos Thy	Interrogatoire de Suos Thy	D61/I-Annex 08.2	E3/445