The Court of Appeal is ruling on whether the Home Secretary has the legal power to take away the right of nine Afghan hijackers to work and enjoy other freedoms in the UK.
A QC for John Reid argued that, although the nine could not be deported because of their human rights, immigration law allowed him to impose "temporary admission" status on them and curb their freedom while they remained in the country.
The Master of the Rolls, Sir Anthony Clarke, Lord Justice Brooke and Lord Justice Neuberger, are due to announce their decision in London.
The nine Afghans hijacked a Boeing 727 on an internal flight in Afghanistan in February 2000 and forced the crew to fly to Stansted in Essex. They were fleeing the Taliban regime.
Although they were refused asylum, a panel of adjudicators ruled in 2004 that, under Article 3 of the European Convention on Human Rights, they could not be sent back to Afghanistan because their lives would be endangered.
Following a public outcry over the nine being granted a "hijackers' charter", successive Government ministers attempted to restrict their rights.
They were eventually granted only temporary admission in November 2005 by the then Home Secretary Charles Clarke.
But the Home Office suffered an embarrassing High Court defeat in May this year when Mr Justice Sullivan ruled that it was unlawful under the 1971 Immigration Act to keep the nine on temporary leave.
The judge declared they were entitled to "discretionary leave" to enter and remain in the UK, subject to review every six months.
The nine - Reshad Ahmadi, Abdul Shohab, Abdul Ghayur, Taimur Shah, Nazzamuddin Mohammidy, Mohammed Kazin, Ali Safi, Mohammed Safi and Mohammed Showaib - say they are educated people who do not want to "sponge" off the state.
PM Tony Blair called the High Court ruling an "abuse of common sense".