The three Court of Appeal judges on Wednesday wrapped up an appeal hearing for Rurik Jutting, who is serving a life sentence for the 2014 killings in the Chinese financial center.
The judges are to issue their decision at a later, unspecified date, after listening to a day and a half of submissions from defense and prosecution lawyers.
Jutting’s legal team argued that the trial judge gave incorrect instructions to the jury on deciding the verdict.
Cambridge University-educated Jutting, 32, was convicted last year by a nine-person jury of the brutal killings of Seneng Mujiasih, 26, and Sumarti Ningsih, 23.
Jutting spent days torturing one of the victims while snorting cocaine and then stuffed her body into a suitcase left on his balcony.
Jutting did not deny the killings but argued he was guilty of manslaughter, not murder, because he was acting under diminished responsibility resulting from several psychiatric disorders.
His appeal lawyers said the trial judge misled the jury in instructing them on how to assess if Jutting had an “abnormality of the mind” that substantially impaired his mental responsibility. Under Hong Kong law, that can be used to justify a manslaughter conviction in a killing.