The Labour Chair of the Joint Committee on Human Rights, Harriet Harman, said: The Bill provides a clear and transparent basis for powers already in use by the security and intelligence services, but there need to be further safeguards.

[23] On 21 December 2016, the European Court of Justice (ECJ) declared that the generalised retention of certain types of personal data is unlawful, although little is known as to how this will affect the Investigatory Powers Act at this stage.

[48] In January 2019 the Home Office blocked the appointment of Eric King as head of investigations at IPCO, citing national security grounds.

[53] The draft Bill generated significant public debate about balancing intrusive powers and mass surveillance with the needs of the police and intelligence agencies to gain targeted access to information as part of their investigations.

[57][58] Privacy campaigners say the bill clearly lays out the mass surveillance powers that would be at the disposal of the security services, and want it amended so that the surveillance is targeted and based on suspicion and argue that the powers are so sweeping, and the bill's language so general, that not just the security services but also government bodies will be able to analyse the records of millions of people even if they are not under suspicion.

[60] Dominic Grieve later clarified the extent of these freedoms, "the principle of the right to privacy against the state is maintained except if there is a good and sufficient reason why that should not happen.

"[62] The Register argued the Act enshrines parallel construction in law and allows the state to lie about the origins of evidence in court, treating it as infallible, and prohibit the defendant from questioning it.

[64] The Chinese government cited the Snooper's Charter (officially the Draft Communications Data Bill) when defending its own intrusive anti-terrorism legislation.

[53] Recent Wikileaks articles suggest that phone and digital device tracking both direct and indirect (e.g. FM radio blipping via Android exploit) also mentioned in Register posts by "Anonymous Coward" to covertly follow subjects have been used in the past but for operational reasons it is not clear if they are still used.

The original poster has since decided to cooperate with the authorities and not comment further publicly on this subject, though the technique was independently rediscovered before the article in question was released.

Silkie Carlo, policy officer at Liberty, said: The powers we're fighting undermine everything that's core to our freedom and democracy — our right to protest, to express ourselves freely and to a fair trial, our free press, privacy and cybersecurity.

[72][73] On 7 February 2025, US media reports revealed that Apple Inc had received a "technical capability notice" under the Act, ordering them to break the encryption on iCloud backups worldwide.