Proposed new snooping laws are unclear, lack sufficient privacy protections and fail to cover all the intrusive powers used by spy agencies, a parliamentary inquiry has concluded.
In a blow to the Government's hopes of securing smooth passage for the landmark Investigatory Powers Bill, the influential Intelligence and Security Committee said it was "handicapped from the outset".
It said the proposals in their current form represent a "missed opportunity" and called for ministers to make a number of substantial changes.
It described the approach in the Bill towards security services' examination of communications data - the who, when and where but not the content of an email or phone call - as "inconsistent and largely incomprehensible".
Tory MP Dominic Grieve, chairman of the committee, said: "The issues under consideration are undoubtedly complex, however it has been evident that even those working on the legislation have not always been clear as to what the provisions are intended to achieve."