Major investigation and public protection

First response and the national referral mechanism

Duty to notify

As detailed by section 52 of the Modern Slavery Act, frontline staff employed by the police, local authorities, National Crime Agency and the Gangmasters Licensing Authority have a duty to notify the Home Office if they encounter a potential victim of modern slavery in England and Wales. Frontline staff employed by UK Visas and Immigration, Border Force and Immigration Enforcement must also comply in accordance with Home Office policy. For further information see Making a referral.

This duty is intended to help build a more comprehensive picture of the nature and scale of modern slavery.

First responders

First responders are agencies and organisations with a responsibility to identify and interview a potential adult or child victim of modern slavery. The first responders are:

Responding to all potential victims

Frontline officers and staff should first take immediate and effective steps to ensure that a person suspected of being enslaved is made safe.

If the person making initial contact with a potential victim, witness or third party does not have the requisite knowledge or expertise to sensitively handle vulnerable and traumatised individuals, they should refer to their line manager or duty officer immediately. The line manager or duty officer is responsible for progressing and arranging a referral into the NRM.


When a suitably trained first responder becomes aware of a potential victim, they should make arrangements for specialist interviewers at an early stage. Trained officers should interview potential victims, whether adult or child, in accordance with Ministry of Justice (2011) Achieving Best Evidence in Criminal Proceedings: Guidance on interviewing victims and witnesses, and guidance on using special measures. The questions should be open to avoid accusations that the person has been led or influenced.

If there is a possibility that the person is a victim, the interview should take the exploitation indicators into account, and the information derived from the interview should be used to complete a national referral form. A suitably trained first responder with the requisite knowledge and expertise should complete the form for a potential victim of modern slavery, and submit this to the Modern Slavery Human Trafficking Unit (MSHTU).

It takes courage and time for a victim to make a disclosure. In cases where a plausible disclosure is not imminent, it may be appropriate to seek local temporary accommodation. This is chargeable to the referring agency. Victims should be placed in secure accommodation and be made to feel comfortable enough to consent to a referral into the NRM. They should be under strict instructions not to attempt communication with their exploiter(s) or other victims. The placement should be kept confidential.

The presence of children at an interview can affect the ability and willingness of victims to disclose information about their experiences, especially when these have been violent or of a sexual nature. Officers and staff should make arrangements for the interview to take place in private while safeguarding the children. The victim is also likely to have been coached by their exploiter(s) and may be prepared with a story to tell the authorities.

As a first responder, the police service should complete the actions described in this section to identify potential victims of modern slavery, and make referrals into the NRM from the point of investigating an allegation.

For further advice, contact your force modern slavery single point of contact (SPOC) officer or dedicated modern slavery investigations team.

Responding to potential child victims

A potential victim under the age of 18 years must be represented by an appropriate adult or child advocate, who should be carefully selected. It may not be in the best interests of a child to be interviewed at an early stage of their discovery or during initial contact with authorities. It is important that the child is placed in appropriate secure accommodation before being interviewed.

To determine whether or not a child is a victim of modern slavery, it is not necessary to prove that they have been compelled or induced.

Age assessment

Where the age of a potential victim is uncertain and there are reasons to believe that the person is a child, they should be presumed to be a child and receive immediate access to protection, support, accommodation and advice, as stipulated by section 51(2) of the Modern Slavery Act 2015. If the potential victim looks older than the age they claim to be, a request should be made to a suitably trained social worker, nurse or approved mental health professional for an age assessment. During this process, the child should be represented by an appropriate adult or child advocate and housed in secure accommodation with close adult supervision. Officers should ensure that the child’s placement is kept confidential and that appropriate measures are taken to prevent the child from going missing with the risk of being re-exploited. The assessment should be explained clearly to the child, take place in an appropriate facility and should not be rushed. It must be compliant with the Merton judgment.

Officers should be aware of the potential for an adult to pose as a child to gain access to children, and they should take necessary precautions to prevent this.

The police and the local authority children’s services should be contacted immediately when a first responder suspects that a child is a victim of modern slavery. Local authority children’s services are the primary service providers for safeguarding and responding to the needs of a child victim of modern slavery, regardless of their nationality or immigration status. They support the child and prompt a criminal investigation.


Child victims of modern slavery are amongst the most vulnerable, the easiest to control and the least likely to admit to their situation. They may not show obvious signs of distress, as they may not realise that they have been enslaved or see themselves as being at risk of harm and in danger. Parents and relatives may also be involved in the exploitation of the child. Children are likely to be extremely loyal to their parents or carers so it is not likely that they will, of their own initiative, seek protection against such people.

It is also possible that a child’s experiences of modern slavery perpetrated by adults, and experience of corruption and abuse by police, officials and/or authorities in their home countries, may make them wary of all adults, including police officers. They may, therefore, be reluctant to disclose any information in an interview until they have built a trusting relationship with those interviewing.

Interviews should take place in a child-friendly environment. During the interview, the child should be asked what measures would make them feel safe, how they perceive authority figures and people in uniform, and the police should clearly explain their role to the child. The child should be provided with emergency contact numbers, including 999, and know that these are free of charge.

If a child is housed and goes missing before or after the interview, and is suspected of being enslaved or exploited, they should be treated as a missing person. A suitably trained person should conduct a debrief.

Unaccompanied children

Some children who are under the control of a trafficker may say they are unaccompanied. They might have entered the UK with a trafficker who may or may not be a family member. In such cases, the trafficker may have told the child that if they say they are unaccompanied, they will be granted permission to stay in the UK and be entitled to claim welfare benefits.

Responding to perpetrators who may also be victims

Section 45 of the Modern Slavery Act 2015 introduces a statutory defence for slavery or trafficking victims who commit certain offences, if it can be evidenced that they were compelled to commit the offence as a result of exploitation. The defence in section 45 does not, however, apply to victims who have committed offences outlined in Schedule 4 of the Act.

If a person is arrested and so enters the criminal justice system as a perpetrator, and officers discover during the PACE interview that the person committed a modern slavery offence through coercion and may also be a victim, the interview should continue and evidence be obtained. On conclusion of the interview, the person should be referred into the NRM if they consent. If appropriate, the person should be bailed for the offence under investigation. If, however, the person has been arrested for an offence outlined in Schedule 4, is illegally residing in the UK and is likely to abscond, bail should be withheld. Following the referral, a victim debrief and a subsequent interview in line with Achieving Best Evidence in Criminal Proceedings: Guidance on interviewing victims and witnesses, and guidance on using special measures should take place to identify additional perpetrators and to help officers gather further evidence. Refer to the MSHTU for tactical advice on +44 (0)84 4778 2406.

National referral mechanism

The national referral mechanism (NRM) is a gateway for locating and identifying potential victims of modern slavery and ensuring that they receive the appropriate protection, support, accommodation and advice. It is designed to facilitate all agencies which could be involved in a modern slavery case to share information about and assist potential victims.

Any potential child victim must be referred into the NRM automatically. Any potential adult victim must sign their consent before they can be referred.

The NRM was introduced in 2009 to meet the UK’s obligations under the Council of Europe Convention on Action against Trafficking in Human Beings.

It is also the mechanism through which the MSHTU collects data about victims. This information contributes to building a clearer picture about the extent of modern slavery in the UK. Recording and investigating responses to the NRM is essential to assist with national mapping, identifying hot spot locations, highlighting intelligence on source countries, and to address immigration support issues.

A review of the NRM took place in 2014 (see Further information) and a new process is currently being developed. This APP will be updated accordingly.

Making a referral

There are two ways to make a referral and satisfy the duty to notify.

1. Send an NRM form to the MSHTU

  • Potential adult victims can only be referred in this way if they give written consent to the referral.
  • Potential child victims must always be referred in this way.
  • A suitably trained officer or staff member with the requisite knowledge and expertise should complete and submit the NRM form to
  • There are two types of referral form: one for children and one for adults.
  • Both referral forms list indicators of potential modern slavery and ask for evidence to support the concern that a person may have been enslaved.
  • There should be sufficient information in the form to enable the MSHTU competent authority (CA) to make an informed reasonable grounds decision regarding the victim’s status.

2. Send an MS1 form to the Home Office

  • If a potential adult victim does not consent to a referral into the NRM, complete an MS1 form and send it to the duty to notify inbox at
  • The MS1 form should be completely anonymous if the potential victim does not consent to their details being shared.
  • Unless there are exceptional circumstances, the MS1 form should be sent as soon as is practicable and within one month of encountering a potential victim.
  • Sending a duty to notify MS1 form should not be relied upon to safeguard victims. Existing safeguarding processes should still be followed in tandem.


Guidelines for completing a national referral form

For all potential victims

  • Provide as much detail as possible.
  • Be honest in your evaluation.
  • Write clearly and concisely.
  • Provide details, including contact numbers and email addresses of all those who will be handling the referral.

For adults

  • Consent must be obtained as a signature on the form. Without consent and a signature, the referral will not be accepted. Potential victims should be made to feel comfortable enough to consent to a referral.
  • The potential victim should also sign on the referral form if they would like their details to be passed to The Salvation Army in England and Wales, Trafficking Awareness Raising Alliance (TARA) or Migrant Help in Scotland and Northern Ireland for the purposes of arranging secure accommodation and access to support services tailored to their individual needs, eg, counselling.
  • With the victim’s consent, make a referral by telephone to The Salvation Army, TARA or Migrant Help before, or at the same time as, sending the referral form.
  • An interpreter should be considered, where necessary, to ensure that the potential victim understands the information provided to them.

For children

  • A child does not need to consent to be referred, but it is best practice to consult with them and explain the process.
  • Children must be represented by a carefully selected appropriate adult or a child advocate.
  • An interpreter should be considered to ensure that the child and appropriate adult or child advocate understand the information provided to them.
  • A copy of the NRM form should also be sent to local authority children’s services at the same time as it is sent to the competent authority.
  • For further information see the London Safeguarding Children Board (2011) London Safeguarding Trafficked Children Toolkit.

Referring a child into the NRM is beneficial because it helps local authority children’s services to ensure that the child’s needs are addressed and that any risks are highlighted and mitigated.

Competent authorities

The Modern Slavery Human Trafficking Unit (MSHTU) and the Home Office are the two designated competent authority decision makers under the national referral mechanism. This may change for pilot cases. All completed NRM forms should first be sent to the MSHTU.

The MSHTU deals with all cases relating to European Economic Area (EEA) nationals. This includes referrals from the police, the Home Office, local authorities, charities and non-governmental organisations (NGOs).

The Home Office handles referrals from non-EEA countries identified as part of the immigration process, eg, where trafficking may be part of an asylum claim.

After the form has been sent, the first responder should maintain regular contact with the competent authority to share new information and to remain up-to-date with the case.

Note: completing the form and awaiting an outcome should not delay an investigation. From the point that a crime is disclosed, potential victims should be updated regularly about the investigation.

After the CA has received the referral form, trained case owners assess the case and decide whether or not an individual referred to them is a victim of modern slavery. It is also a way to provide secure and appropriate accommodation, health and welfare support to those in need.

National referral process

The national referral process has two stages:

Stage 1 – Reasonable grounds decision

The case manager works to the following reasonable grounds threshold:

From the information available so far, I believe but cannot prove that the individual is a potential victim of modern slavery.

If a reasonable grounds decision is delayed and takes longer than five days, and the potential victim of trafficking is destitute, they can be entered into an Adult Human Trafficking Victim Care and Coordination Contract funded by the UK government via The Salvation Army. Accommodation and outreach services for potential victims are provided through this contract.

Recording the reasonable grounds decision

Page 53 of the Home Office (2016) Victims of modern slavery competent authority guidance states that staff must keep a detailed consideration minute. When issuing a negative decision, the CA must use this consideration minute as the basis for dealing with the key points in their decision. When issuing a positive decision, the CA must keep this minute on file.

The consideration minute must include all of the following:

  • immigration history and case summary
  • objective information on country in question
  • findings of fact with detailed reasoning (clear credibility findings including reference to which events the CA accepts took place and which events the CA does not accept took place)
  • why the definition of human trafficking or modern slavery is or is not met in respect of a reasonable grounds test
  • decision outcome
  • date of decision.

Where the assessment of credibility undermines an individual’s account to the point that the reasonable grounds standard of proof is no longer met, it should be concluded that the individual is not a victim of modern slavery.

Positive reasonable grounds decision

When a positive reasonable grounds decision is made, the referred person and the first responder are both notified by letter of the decision. The potential victim is granted a recovery and reflection period of at least 45 days during which they may receive accommodation and/or support under an Adult Human Trafficking Victim Care and Coordination contract. This time allows the victim to begin recovery from their ordeal and to reflect on the next steps, including deciding if they wish to assist the police with their investigation.

Additional considerations for potential child victims

For referrals of suspected child victims of modern slavery, the first responder can request an extension to the 45-day period. The CA must make its decision in the best interests of the child. Children will be supported by local authorities, whose duties will not cease if there is a negative conclusive grounds decision.

Secure accommodation

If the competent authority (CA) has reasonable grounds to believe someone is a victim of modern slavery, the Home Office is obliged to make sure that the accommodation provided for them is appropriate. This means accommodation must meet the support needs of victims and be secure enough to make sure that they cannot be exploited again. For example, accommodation may be deemed to be secure if it is in a different location from where the victim was exploited. Some victims may, however, require more comprehensive security or support arrangements.

The factors to consider are the:

  • victim’s level of trauma
  • exploiter’s level of sophistication
  • exploiter’s desire to re-exploit the victim.

Specialist accommodation can be arranged through The Salvation Army by calling their 24-hour referral line on +44 (0)30 0303 8151.

Negative reasonable grounds decision

If the reasonable grounds decision is negative the CA will close the case, but the police investigation must continue. If new substantive evidence emerges, it can be submitted to the CA for the decision to be reviewed.

Stage 2 – Conclusive grounds decision

During the minimum 45-day recovery and reflection period, the competent authority (CA) gathers additional information relating to the referral from the first responder and other sources. Close collaboration between the police and the CA is required.

This additional information is used to make a conclusive grounds decision on whether or not the referred person is a victim of modern slavery.

The case manager works to the following conclusive grounds threshold:

On the balance of probability, it is more likely than not that the individual is a victim of modern slavery.

According to page 64 of Home Office: Victims of modern slavery – Competent authority guidance, version 3.0, the expectation is that a conclusive grounds decision will be made as soon as possible following day 45 of the recovery and reflection period. There is no target to make a conclusive grounds decision within 45 days – the timescale will be based on all the circumstances of the case.


Extensions to the 45 days can be granted where necessary. Reasons for an extension can include the victim suffering from serious health issues; severe mental health or psychological issues (including post-traumatic stress disorder) requiring a longer period of recovery and reflection; or high levels of victim intimidation.

The length of the extension will be considered on a case by case basis depending on the facts of the individual case.

If the 45 day recovery and reflection period has been extended, the competent authority, first responder and support provider must keep the extension under review. An extension review must occur every 28 calendar days or when there is a change in the victim’s circumstances.

For further information see page 94 of Home Office: Victims of modern slavery – Competent authority guidance, version 3.0.

Positive conclusive grounds decision

Both the first responder and the victim are notified of this decision.

When a person is found conclusively to be a victim and has agreed to assist the police with formal enquiries in the UK, the police may make a formal request to the Home Office for them to be granted a period of discretionary leave to remain (DLR) on this basis. The period must not be less than 12 months and one day, and no more than 30 months. This may be extended where necessary, for example, when a criminal prosecution takes longer than expected and the police have confirmed or requested an extension. Both EEA and non-EEA nationals can apply.

As a result of Galdikas & Ors, R (on the application of) v Secretary of State for the Home Department & Ors (Rev 1) [2016] EWHC 942 (Admin) (26 April 2016), the Home Office also accepts applications for DLR from confirmed victims of modern slavery or their legal representatives. This only applies if victims are helping the police with their enquiries.

Requests for discretionary leave to remain

Any requests for discretionary leave to remain (DLR) of a modern slavery victim should be sent to:

After the request is made, the competent authority (CA) may seek further information from the confirmed victim such as asking them to complete an application form (FLR(O) or FLR(DL) as appropriate) and return it to the CA. No decision on whether to grant discretionary leave will be taken before a conclusive grounds decision is made. A victim cannot be prevented from leaving the UK if they so wish.

For further information see UKVI guidance on discretionary leave.

Negative conclusive grounds decision

If the CA decides that the referred person was not enslaved, the criminal investigation should still continue. If there are no other circumstances that would allow the referred person the right to live in the UK, they are supported by the government to return voluntarily to their country of origin.

Alternatively, a limited number of rescue and rehabilitation centres are provided by charities and non-governmental organisations for those who fall outside the NRM or who refuse consent for referral. Those who initially refuse consent may change their decision following their stay, and can then be referred to the UKHTC. Temporary accommodation providers include:

A victim claiming asylum may also be entitled to accommodation provided by the National Asylum Support Service (NASS).

There is no statutory right of appeal for potential victims against an NRM decision. However if a person can provide further details in ongoing assessments, others can on their behalf, or new substantive evidence emerges, the CA can be requested to reconsider their decision. Decisions can only be challenged through judicial review.

Additional considerations for children

Following a negative reasonable grounds or conclusive grounds decision, children may still have safeguarding needs, especially if they are unaccompanied and seeking asylum.

Practitioners should, therefore, ensure that a negative NRM decision does not have an adverse impact on children’s care and does not override the statutory duty placed on local authorities by the Children Act 1989.

Page last accessed 09 April 2020