Judgement on the jail sentences imposed on a man and woman who raped a 12-week-old baby has been reserved.
Alan Webster and Tanya French pleaded guilty
Alan Webster, 40, was sentenced to life with a six-year minimum before being considered for parole, and Tanya French, 19, was jailed for five years.
The pair, both from Hatfield, in Herts, pleaded guilty to raping the girl.
Attorney General Lord Goldsmith said the offences were of the "gravest depravity" and urged Court of Appeal judges to increase the jail terms.
The Government's senior law officer told Wednesday's hearing the crimes committed by Webster and French had "shocked and outraged public opinion".
Lord Goldsmith QC asked the five-judge panel, headed by the Lord Chief Justice, Lord Phillips, to rule the sentences currently being served by the pair were "unduly lenient".
Webster was jailed at St Alban's Crown Court after pleading guilty to rape, indecent assault, permitting indecent images to be taken of a child and making indecent images. French, 19, admitted the same charges.
Webster and French raped the baby girl she was babysitting and took photographs of the abuse.
When allowing the appeal, Lord Justice Rose said it raised "fundamental" questions in relation to double jeopardy - when a defendant faces sentencing twice - and in relation to discounts for pleas of guilty.