Judges will "properly reflect" before making a decision on whether to reduce child-killer Aaron Campbell's prison sentence.
Campbell, 17, brutally killed Airdrie schoolgirl Alesha MacPhail on his native Isle of Bute last summer.
He was unanimously convicted by a jury of the horrendous crimes.
Campbell, who was 16 when he killed Alesha, 6, appeared via video-link to Edinburgh High Court today as his solicitors argued that the 27-year sentence he was given is too much.
Alesha's mum had previously labelled Campbell's intention of having his sentence reduced as "laughable".
His legal team acknowledged the "appalling" and "heinous" nature of his actions as Campbell showed no emotion, staring into the camera while dressed in a black-polo shirt.
His solicitor told the court Campbell will be 43 before being considered for release and said: "The question of whether he will be released will depend on the view of the Parole Board and upon them reaching a conclusion that it would be safe to release him.
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"I accept, as does the appellant, that day may never come.
"Due to the appellant's age, the punishment selected was excessive and amounts to a miscarriage of justice."
He added: "If one maintains a punishment period as it is then the appellant will be 43 years of age before the issue (of his release) is perhaps considered to any degree.
"The appellant will have been in custody for the entire period he has been on this Earth, plus another 11 years."
The lawyer went on to argue the sentencing judge had overly-focused on "pessimistic" background reports when choosing the minimum jail term.
He said: "In placing so much emphasis on the negative prospects of reintegration, this effectively disallowed the opportunity for progress to be made up until that period.
"When one is dealing with a child, it would make much more sense to give that opportunity because one knows there's the ultimate arbiter of whether someone is or can be rehabilitated into society with the Parole Board."
Campbell sat rigidly with his arms at his side during the entire hearing and stared blankly into the camera at Polmont.
When the appeal concluded, the judges said they will take a "considerable amount of time" to "properly reflect" before making a decision.
