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Migration and security: Navigating the risks

17 Feb 2015

‘Control’ and ‘security’ have moved to being central concerns in political and media narratives about migration in the UK. This trend is exemplified by the fact that since February 2014 ‘immigration and security’ has existed as a single ministerial portfolio – held by James Brokenshire – even though in many respects, immigration policy and security are entirely different briefs. Brokenshire’s responsibilities include issues as divergent as international counterterrorism initiatives and refugee integration. But security is nonetheless a persistent theme in immigration debates, particularly after media coverage of crimes perpetrated by migrants or members of distinct diaspora communities, or acts of terrorism involving these groups.

Where does security fit in the migration debate?

‘Security’ can be defined as the ‘state of being free from danger or threat’, although the types of dangers or threats people have in mind when they use the term vary widely and the boundaries as often blurred. The Security Service, MI5, aims to protect ‘national security’ with a particular focus on threats such as terrorism. The term ‘border security’ typically encompasses a much wider range of goals, from preventing the entry of serious criminals to identifying attempts to circumvent immigration rules. Visa and citizenship applications, meanwhile, combine scrutiny of applicants’ backgrounds for serious crimes that carry multi-year sentences with an assessment of their ‘character, conduct or associations’ that can lead to a visa refusal, even in the absence of criminal convictions. This commentary uses the term ‘security’ to refer to protection against both terrorist threats and criminal offences, while recognising that important distinctions exist between the two and that crimes vary enormously in their severity.

Evidence suggests that, on average, non-UK born individuals are no more likely to commit criminal offences than the UK born. However, because most noncitizens do not have the same freedom to come to or remain in the UK as British citizens, there is an expectation that policymakers will exclude foreign nationals who pose threats.

Acts of terrorism are also not committed only by foreign nationals. A number of recent major terrorist attacks or plots in the UK – including the devastating 7/7 attacks on tube trains and a bus – have been perpetrated by British citizens, and as of 30 September 2013, 120 people were in custody in the UK for terrorism related offences, 79% of whom were British nationals.

Recent debates about UK national security have also focussed on managing the threat posed by British Islamist fighters returning from Syria and Iraq. At the same time, foreign national perpetrators of terrorist attacks will not necessarily be accurately classified in data as ‘migrants’ – they may be in the country as tourists or visitors of some other type. This complicates attempts to clearly show a relationship between migration and terrorism.

Nonetheless, media reports and parliamentary questions typically revolve around three key questions relating to three stages of the migration process:

  1. Entry: Why the British state allowed a potentially dangerous individual to enter the country?
  2. Residence: What does (or should) the state know about foreign nationals in the UK?
  3. Removal: Why a potentially or demonstrably dangerous person has not been removed?

The government has several tools at its disposal to address these concerns. But it also faces a major challenge: how to manage the costs of using these tools. Governments in any democratic country face trade-offs between security and freedom, as well as between security and the facilitation of trade and mobility. These involve a complex series of intertwined and sometimes competing demands: complying with international treaties and obligations; preventing long queues at the border; facilitating migrant integration; reducing illegal immigration; and protecting individual liberty, to name but a few.

Of course, any action undertaken by the state invariably costs money, too. Expense incurred by central or regional governments (and therefore taxpayers) in increasing staffing at the UK’s borders, intelligence about the whereabouts of foreign nationals in the UK or enforcement activities to remove those deemed undesirable by the state may thus mean reduced spending on competing priorities.

Security and migrants entering the UK

The government controls entry to the UK in various ways. These include (but are not limited to):

The most visible part of the UK’s efforts to protect national security through immigration controls is the UK border. In addition to physical checks such as screening luggage for explosives and drugs, passengers presenting their passports are also checked against a ‘warnings index’ which identifies whether the individual is considered to be a threat to the UK. Managing the index has been a challenge, and it has been criticised for containing irrelevant or out of date information, as well as for the fact that checks have been suspended under some circumstances.

Many travellers can also be scrutinised before they arrive. The UK’s National Border Targeting Centre collects advance information about passengers to be checked against various watch lists.

Travellers from most countries outside the European Union are also vetted in advance through the visa allocation process. Visas provide permission to enter the UK and remain for a defined period and for defined purposes. Before issuing a visa the government can require individuals to provide evidence that that they are not likely to be a threat to, or an economic burden on, the UK.

As part of the application, prospective visa holders must answer a series of questions. These include factors ranging from whether the person has been refused a visa or deported from any country in the past, whether they have been convicted of criminal offences or involved in terrorism, and whether there are any other activities that indicate they are not of ‘good character’.

Constraints and limitations of entry checks

Identifying whether a potential visitor to the UK is of ‘good character’, that the documents they provide are authentic or that have been honest about their reason for travelling to the UK, is not a straightforward task. It requires both an investment of time by British officials scrutinising this evidence and reliable official data (such as criminal records) in other countries. A person intending to commit a crime or act of terrorism in the UK is unlikely to admit it and will not necessarily have a criminal past, or be known to British or foreign security services.

In other words, scrutiny of people entering the UK can reduce security risks but cannot be expected to eliminate them entirely. In addition, the more watertight the process is designed to be, the higher its costs – including operational expenses and the potential costs of reduced tourism and travel to the UK that could result from lengthy screening procedures. The UK border is crossed more than 100 million times each year, with less than 1% of those crossings for the purpose of migration, either into or out of the UK. This vast volume of travel makes thorough checks of every border crosser impractical.

The UK’s total gross budget for immigration and borders operations in 2014-15 is a total of £1.8 billion, according to the National Audit Office. This has to cover, among other things: the management of applications to enter the UK; border controls; activities dealing with people who have already entered the UK, such as asylum applications, visa renewals and extensions; immigration enforcement and the process of removing people from the UK. (This sum does not cover the costs of the intelligence or police services which may also be involved in surveillance and enforcement.)

Another constraint is that residents of EU member states entering the UK face considerably less scrutiny than non-EU visitors or migrants because of the EU’s freedom of movement directive. EU nationals with criminal records are not automatically refused entry to the UK or removed on the basis of their past criminal activity. EU nationals can be removed or denied entry only under certain circumstances, such as a ruling that they pose a threat to national security.

Security and foreign nationals in the UK

Most Migration Observatory materials deal with foreign-born people, but ‘foreign nationals’ are a more useful group to consider for the purposes of this discussion, since UK immigration controls do not ordinarily apply to British citizens in the UK.

Once a foreign national has entered the UK they may be required to register with the police within a week and to provide proof of their address and the terms of their visa. This currently applies to nationals of the following countries: Afghanistan, Algeria, Argentina, Armenia, Azerbaijan, Bahrain, Belarus, Bolivia, Brazil, China, Colombia, Cuba, Egypt, Georgia, Iran, Iraq, Israel, Jordan, Kazakhstan, Kuwait, Kyrgyzstan, Lebanon, Libya, Moldova, Morocco, North Korea, Oman, Palestine, Peru, Qatar, Russia, Saudi Arabia, Sudan, Syria, Tajikistan, Tunisia, Turkey, Turkmenistan, United Arab Emirates, Ukraine, Uzbekistan, and Yemen.

For all other nationalities there is no formal mechanism to trace their whereabouts during their stay in the country. However, the Metropolitan Police now routinely checks the immigration status of people arrested and taken into custody as a part of Operation Nexus, and where there are significant concerns about an individual, the police or intelligence services such as MI5 may also monitor them.

Foreign nationals who are in the UK and are applying for indefinite leave to remain or for UK citizenship must also undergo background checks, which includes scrutiny of criminal convictions and whether the person is considered a threat to national security.

Despite pressure on successive governments to collect complete records of whether people have left the country, checking 100% of passengers leaving the country has historically been difficult in practice, making it difficult to know whether people who entered the UK on a temporary visa left when it expired.

This partly explains the ‘migration refusal pool‘ – a list of people who have been refused permission to remain in the UK but who may (or may not) have remained in the country without permission. This list stood at 174,000 in mid 2014.

The lack of knowledge about where many visitors to the UK are staying, and whether they have remained in the UK or left, has contributed to media narratives about a decline in public confidence in the UK immigration system. That said, while overstayers violate UK immigration law, it is not clear whether better information about these individuals would improve the governments’ ability to protect the public from crime or terrorism.

Security and the removal of people from the UK

The removal of foreign nationals from the UK can take place when a foreign national does not have legal grounds to remain in the country, has committed a serious crime or is considered to be a threat to the security of the UK. Removals can be voluntary or enforced, and most removals are simply related to the immigration status of the person in question.

In situations where a serious crime has been committed deportation is often automatic. The government specifies that deportation should apply to a non-EU citizen who committed a crime that led to a custodial sentence of 1 year or more, and to an EU citizen who received a custodial sentence of two years or more. Over the course of 2013, 4,667 foreign criminals were deported from the UK. The government can also issue deportation orders where foreign nationals are deemed to pose a significant threat to the national security of the UK.

However, even these processes are not as straightforward as they might seem. A recent National Audit Office report suggested that removing foreign national offenders is ‘inherently difficult’ due to legal barriers and the unwillingness of many countries to receive offenders back home. For example, deportation may breach the 1951 Refugee Convention (by, for example, exposing that person to the risk of torture or death) or the 1950 European Convention on Human Rights (by, for example, leading to a ‘disproportionate’ interference with private or family life).

High profile cases – such as that of Abu Qatada, who managed to avoid deportation from the UK to Jordan for eight years on the basis that he would face an unfair trial with evidence obtained by torture  – regularly highlight the fact that removals can be difficult for ethical reasons. Foreign nationals suspected of involvement in terrorism may well come from states with repressive regimes, ‘failed’ states or those in the grip of civil war, making it effectively impossible for the UK to send them back there – or perhaps creating further risks to the UK by losing track of potentially dangerous individuals who pose a known threat to the country.

The NAO report also argued that ‘poor administration’ had played a part in slow progress to removing foreign national offenders.


The vast majority of people perpetrating crimes in the UK are UK nationals, as are a majority of people arrested or imprisoned for terrorism-related offences. But when foreign nationals pose a threat there is an understandable response of anger and frustration. The idea that someone has been able to enter the UK and attacked its people is a highly emotive subject.

Preventing potentially dangerous people from entering the UK requires complex and detailed intelligence. Governments’ capacity to collect this information at reasonable cost and without imposing significant burdens on the vast majority of legitimate travelers is inevitably constrained. Equally, the process of keeping track of foreign nationals in the UK, or of removing dangerous individuals from the country, is sometimes limited by practical, ethical and legal challenges.

As in any area of public policy, there is always scope for improving intelligence gathering and reducing risk. But the goal of excluding foreign nationals who pose a threat to security is impossible to deliver with certainty.

With thanks to Seema Farazi and Ian Robinson at Fragomen for providing information about entry checks and to Myriam Cherti and Bridget Anderson for comments on a previous draft.

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