(CNN) -- Lawyers for a man who ran a notorious torture prison in Cambodia where more than 14,000 people died during the 1970s Khmer Rouge regime are appealing his conviction. The lawyers for Kaing Guek Eav, alias Duch, say he should be acquitted since he was "a witness of the events of the relevant period" and should be in witness protection -- not detention. Duch was convicted of war crimes, crimes against humanity, murder and torture in July in a U.N.-backed war crimes tribunal also known as the Extraordinary Chambers in the Courts of Cambodia. Duch's lawyers also say the court did not have jurisdiction, the appeal states.
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Attorneys: Duch was "a witness of the events" and should be in witness protection
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Duch is convicted of war crimes, crimes against humanity, murder and torture
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Prosecutors: 30-year sentence is too light
The tribunal began its work in 2007 after a decade of on-and-off negotiations between the @placeholder and Cambodia over the structure and functioning of the court.