Prosecutors are urging the court to lengthen Oscar Pistorius' jail sentence.
State prosecutor Andrea Johnson said the judge "overemphasised" Pistorius' disability and gave him a "shockingly lenient" sentence.
Pistorius was sentenced to six years behind bars in 2016 for shooting his model girlfriend Reeva Steenkamp multiple times through a toilet door in 2013.
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The double-amputee Olympic runner's disability played a part in his short sentence, who claimed he mistook Ms Steenkamp for an intruder hiding in the bathroom.
Ms Johnson, who is leading an appeal for a tougher prison term, told South Africa's Supreme Court it was a "senseless killing" and his sentence should be extended to 15 years.
"There is no true, gut-wrenching remorse," she added to the five-judge panel.
Ms Johnson said his disability was exaggerated in last year's trial.
But at the time, defence lawyer Kelly Phelps had argued it had to be a factor.
"Of course his disability is mentioned, but it can't not be mentioned... We can't magic away his disability."
If the Supreme Court agrees with prosecutors, Pistorius could remain locked up until after he is older than 40. It could take the court a couple of weeks to reach a decision.
If successful, it will be the second time Judge Thokozile Masipa has had a ruling in the Pistorius case overturned. She initially ruled he was only guilty of manslaughter, which was overturned and upgraded to murder.