Two former cabinet secretaries have backed the government's efforts to protect civil rights in the war on terrorism.

In his maiden speech in the upper house on Wednesday, Lord Wilson told peers that three key safeguards were vital to prevent individual freedom being eroded.

Government agencies had to respect of liberty and due process, independent watchdogs had to be given access to security reports and parliament had to play a crucial role as a check on the executive.

Wilson, who retired as the Cabinet secretary at the end of last year, said the balance between liberty and rights depended on whether the country was in peacetime or at war.

"The balance between individual liberty and national security do not stay the same," he said.

His comments, in a debate on national security and individual liberty, were echoed by his predecessor Lord Armstrong of Ilminister.

Armstrong, who famously led the prosecution against Spycatcher author Peter Wright, said ministers making decisions on liberty knew they could not abuse the trust of parliament or the public.

Lord Chalfont, who tabled the debate, warned that government attempts to fight terrorism could destroy individual rights to freedom.

"We are in danger of passing the point of balance at which individual liberty can be restricted in pursuance of the common good," he said.