Hindley claims that successive home secretaries, including Jack Straw, have unlawfully condemned her to die in prison without hope of parole. But Mr Pannick told the court: "The passage of time - 32 years - cannot erase the truly horrific conduct with which this appellant was found guilty."
His comments came on the second day of a test case that could affect other killers who have been told that, for them, a life sentence means life.
Mr Pannick rejected mitigation put forward on Hindley's behalf that she was the victim of "intimidation and corruption" by her co-accused Ian Brady and should not be made to suffer the "uniquely severe penalty" of a whole life tariff.
He said: "The Secretary of State simply does not accept that the account now given by the appellant, even if true, provides mitigation which could reduce the proper tariff below that of whole life."
Hindley is held at Highpoint Prison in Suffolk for the murders of Lesley Ann Downey, 10, and Edward Evans, 17.
She was convicted with Brady, now 60, who was additionally jailed for life for murdering 12-year-old John Kilbride.
Another 21 years went by before the pair confessed to killing Pauline Reade, 16, and Keith Bennett, 12, and burying their bodies on Saddleworth Moor, on the edge of the Peak District.
From 1987 onwards Hindley claimed she had acted under intimidation from Brady, who had threatened her life and those of her sister and grandmother.
On one occasion she had been throttled by Brady, her lawyer, Edward Fitzgerald QC, yesterday told Lord Woolf, Master of the Rolls, sitting with Lord Justice Hutchison and Lord Justice Judge.
The hearing continues today.Reuse content