National Security Act 2023

The National Security Act 2023 represents a comprehensive overhaul of the UK’s legal framework for national security, replacing the outdated Official Secrets Acts of 1911, 1920, and 1939. This new legislation introduces measures to combat a wide range of activities threatening UK security, including espionage, foreign interference, sabotage, and other hostile actions by foreign actors such as assassination. In a government statement, the new powers were described as making the UK the hardest operating environment for malign activity undertaken by foreign actors, with MI5’s Director General calling the Act a game changer for national security. The core provisions of the Act, which took effect on 20th December 2023, are aimed at addressing modern threats with updated legal tools.

Espionage 
The Act introduces several new criminal offences related to espionage, which now include obtaining or disclosing protected information, trade secrets, and assisting foreign intelligence services. The offence of obtaining or disclosing protected information replaces earlier provisions, with harsher penalties—now extending up to life imprisonment. The Ministry of Defence has clarified that this offence could apply, for example, to former UK military personnel sharing sensitive information with foreign governments. Additionally, a new offence relating to the disclosure of trade secrets to foreign entities carries a maximum sentence of 14 years. The offence of assisting a foreign intelligence service extends beyond traditional spying activities, criminalising any conduct that materially helps a foreign intelligence service engage in hostile operations against the UK.

Sabotage
The Act also introduces the offence of sabotage, which is defined as damaging assets (tangible or intangible) for the benefit of a foreign power. This offence covers a wide range of sabotage activities, including cyberattacks and physical damage to infrastructure, with penalties extending up to life imprisonment.

Prohibited Places 
Under the Act, certain sites are designated as prohibited places, making it illegal to enter, inspect, or approach them with hostile intent. The legislation expands this category to include sensitive locations connected to UK intelligence agencies, civil nuclear sites, and even vessels carrying nuclear materials. Offences under these provisions address modern threats like drone surveillance and unauthorised electronic hacking. Penalties include imprisonment for up to three months for breaching these restrictions.

Foreign Interference
The Act also tackles foreign interference in UK political processes. The new offence of foreign interference targets actions by foreign states that aim to undermine the UK’s political institutions, public discourse, or electoral processes. To secure a conviction, prosecutors must prove that the accused’s actions were illegitimate (such as coercive behaviour), aimed toward a harmful goal, and intended to benefit a foreign power. Enhanced penalties apply for electoral offences that involve foreign interference, with sentences reaching up to 14 years.

Foreign Influence Registration 
The Act establishes a Foreign Influence Registration Scheme, requiring individuals to register any political influence activities directed by foreign governments.

Preparatory Conduct
Additionally, a new offence of preparatory conduct criminalises actions taken in preparation for espionage, sabotage, or other serious offences outlined in the Act. This allows authorities to intervene early in suspected plots, even before harmful activities have been carried out.

Enhanced Police Powers
The Act grants police expanded powers to arrest and detain individuals without a warrant if they are suspected of involvement in foreign threat activities. Under Section 27, police can detain suspects for up to 48 hours, extendable to 14 days with court approval. In exceptional cases, detention can be prolonged to 28 days under emergency legislation. Individuals detained under these provisions retain certain rights, including the ability to consult a solicitor, although these rights can be delayed in cases where they might hinder investigations.

Preventive Measures

The Act introduces State Threats Prevention and Investigation Measures (STPIMs), modelled after existing terrorism prevention measures. These allow the Secretary of State to impose restrictions on individuals suspected of involvement in foreign power threat activities. Breaching these measures can result in imprisonment for up to 10 years, particularly if travel outside the UK is involved.

The Act has sparked criticism, particularly from journalists and media organisations concerned about its potential impact on press freedom. Critics argue that the legislation could criminalise investigative journalism, particularly in cases involving whistleblowers or reporting on government activities. Although an amendment proposing protections for journalistic activity was defeated in the House of Lords, the government made some changes to clarify the scope of certain offences. The following sections outline specific powers granted under the Act, focusing on arrest without warrant, preventive measures, and investigative authority.

Section 27: Arrest Without Warrant
Section 27 grants police the power to arrest and detain individuals without a warrant if they are suspected of engaging in foreign power threat activities. Initially, the detention can last for up to 48 hours. However, this period can be extended to a maximum of 14 days with court approval. In exceptional cases, emergency legislation can further extend the detention period to 28 days.

Detainees under this section have the right to inform a named individual of their detention and to consult a solicitor. However, these rights may be delayed if exercising them could interfere with an ongoing investigation. Additionally, biometric data collected during this detention can be retained for up to five years, regardless of whether the individual is eventually charged or acquitted.

Section 39: State Threats Prevention and Investigation Measures (STPIMs)
Section 39 introduces STPIMs, which are designed to restrict the activities of individuals suspected of being involved in foreign power threat activities. These measures are similar to the existing Terrorism Prevention and Investigation Measures (TPIMs) and provide the Secretary of State with the authority to impose a range of restrictive measures.

STPIMs can include restrictions on an individual’s movements, communications, and association with others, among other limitations. The purpose is to prevent or mitigate the risk posed by individuals engaged in activities that threaten national security.

Section 56: Breach of STPIMs
Section 56 makes it an offence for individuals subject to STPIMs to breach any of the conditions imposed upon them without a reasonable excuse. The penalty for such breaches is a maximum of five years’ imprisonment. However, if the breach involves violating a travel restriction that prevents leaving the UK, the sentence can be as severe as 10 years, with limited grounds for claiming a reasonable excuse.

Section 57: Search and Seizure Powers
Section 57 provides authorities with significant search and seizure powers in relation to individuals subject to STPIMs. This includes the ability to search premises, seize items, and conduct personal searches at the time of serving the STPIM notice. Additional searches may be carried out in cases where there is suspicion of non-compliance, absconding, or concerns for public safety. Notably, these searches can be conducted without a warrant, except in cases involving routine compliance checks.

The Act also allows for the retention of items found during these searches for testing and evidential purposes. The sweeping nature of these powers is intended to ensure that individuals under STPIMs cannot easily engage in activities that pose a threat to national security.

Schedule 7, Paragraph 12: Polygraph Testing
Schedule 7, paragraph 12, introduces the use of polygraph testing for individuals subject to STPIMs. Under this provision, the Secretary of State can require individuals to participate in polygraph sessions. The information gathered during these sessions can be shared with intelligence agencies, enhancing the government’s ability to monitor and manage those considered a threat.

In short, the National Security Act 2023 represents a significant expansion of the UK’s national security powers, granting authorities broader capabilities to address threats from foreign states and hostile actors. The new powers, particularly those related to arrest without warrant, preventive measures like STPIMs, and extensive search and seizure authority, are intended to respond to the evolving challenges posed by modern espionage, sabotage, and foreign interference.
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