New terrorism laws being considered by the government are either unnecessary or unjustified, the Conservative shadow home secretary says.
David Davis says the plans are unnecessary
Mr Blunkett wants a debate on lowering the standard of proof needed to obtain a conviction in a terrorism trial.
Such an idea was hardly evidence of "an advance in our justice system", David Davis said on BBC Radio.
Other suggestions - such as holding trials behind closed doors - were already allowed, he said.
He told Radio 4's Today programme that terrorists attacked the west because they "hated our civilisation".
New act merging existing legislation from 2000 and 2001
Standard of proof lowered from "beyond all
reasonable doubt" to "on the balance of probabilities"
Part-secret trials for Britons
Security-vetted judges for sensitive evidence
14 foreign nationals held without trial
He said there was a risk of "throwing away the very freedoms we are fighting
for" - and called the proposals "yet another of David Blunkett's kite-flying operations".
The plans were revealed by Mr Blunkett during his six-day trip to India and Pakistan.
They include keeping sensitive evidence from defendants and closed trials before vetted judges.
Civil rights groups and other politicians have condemned the proposals as shameful and an "affront to the rule of law".