The act makes provision for the use of undercover law enforcement agents and covert sources and the committing of crimes in the undertaking of their duty.

"[12] Lord Macdonald of River Glaven, who served as director of public prosecutions from 2003 to 2008, called for explicit limits on the crimes covered by the Bill.

[13] Reprieve's director Maya Foa said that although "our intelligence agencies do a vital job in keeping the country safe, ... there must be common sense limits to their agents' activities".

[14] Privacy International director and legal office Ilia Siatitsa added that "the public has a right to know what type of criminal acts MI5's policy authorises in the UK.

[26] On the third reading of the bill, on 15 October 2020, 34 Labour MPs rebelled against the order to abstain, including Shadow Ministers Dan Carden and Margaret Greenwood,[27] as well as five parliamentary private secretaries, who all resigned from their frontbench roles.

[28] When the Bill reached the House of Lords in January 2021, peers defeated the government in passing two amendments to curtail use of children, and to stop informants participating in the most serious crimes such as murder, torture, and rape.