He said that using the secret evidence had been part of a plan to get the best information possible.
But under our constitutional system, people are not convicted on secret evidence, with the prosecutor as judge.
He said, "The only thing that keeps secret evidence alive is the politics of fear."
The situation raised concerns about the accuracy of the secret evidence before the court.
The government has also asserted the right to rely on secret evidence in immigration cases.
Immigrants are also entitled to due process of law, the court said, and cannot be tried on secret evidence.
They have been detained for a year on the basis of secret evidence.
He warned against "the possibilities for abuse" in the use of secret evidence.
And so are eight others against whom secret evidence is being used.
The case has even led some immigration court judges to question whether the Government's use of secret evidence is too vague.