Data Visualizations

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Publicly-available data on immigration detention in Hong Kong is extremely scarce. Considering that detention concerns persons deprived of their freedom, the lack of data is markedly concerning.

In the past three years, our team has extensively scoured many sources to collect data on immigration detention and vulnerable migrants in Hong Kong. The results of our efforts are shared here. All sources are referenced.

We screen hundreds of sources to clean and compile data for comparability across time periods and ensure its accuracy. However, in the rare chance that there is an inconsistency, please do not hesitate to contact us through the contact form.

Download the data
Selected datasets have been made available for download. For more information, see here.

Usage and credits
To use the visualizations, screencap the chart and add credit as: “Immigration Detention and Vulnerable Migrants in Hong Kong” research project (2020 – 2023) at The Chinese University of Hong Kong

Last update: 22 Sept, 2023

If you intend to use the data, please read the notes for accuracy.

Table of contents

Preface: About the data

  1. Where did we look for data?
  2. What were some of the challenges?
  3. Notes on measurements and units

Section 1: Immigration detention numbers and demographics

  1. Number of detention cases
  2. Yearly admittance into detention centres

Castle Peak Bay Immigration Centre (CIC)

  1. Average daily population in CIC (yearly)
  2. Average daily population in CIC (monthly)
  3. End of year population in CIC
  4. Admissions into and releases from CIC (Yearly)
  5. Nationality of CIC Detainees (End of year)
  6. Nationality of CIC Detainees (End of month date) NEW
  7. Nationality of CIC Detainees (Yearly) NEW
  8. Age of CIC Detainees (End of year)
  9. Age of CIC Detainees (End of month date) NEW
  10. Gender of CIC Detainees (End of year)
  11. Gender of CIC Detainees (End of month date) NEW
  12. Gender of CIC Detainees (Yearly admittances)
  13. Immigration status of CIC detainees (End of month date), including non-refoulement claimant status NEW
  14. Demographics of CIC Detainees on July 31, 2021
  15. Detainees at CIC in 2021 (monthly demographics)

Ma Tau Kok Detention Centre (MTKDC or MTK)

  1. Average daily population at MTKDC
  2. End of year population in MTKDC
  3. Nationality of MTKDC Detainees (End of year)
  4. Nationality of MTKDC Detainees (End of month date) NEW
  5. Nationality of MTKDC Detainees (Yearly) NEW
  6. Age of MTKDC Detainees (End of year)
  7. Age of MTKDC Detainees (End of month date) NEW
  8. Gender of MTKDC Detainees (End of year)
  9. Gender of MTKDC Detainees (End of month date) NEW
  10. Gender of MTKDC Detainees (Yearly admittances)
  11. Immigration status of MTKDC detainees (End of month date), including non-refoulement claimant status NEW

Length of detention periods – CIC and MTKDC

  1. Length of detention at CIC
  2. Length of detention at MTKDC (categories)
  3. Length of detention at MTKDC (percentage comparison)

Reasons for detention – CIC and MTKDC

  1. Reasons for detention at CIC and MTKDC
  2. Reasons for detention at CIC (grouped sections)
  3. Reasons for detention at CIC (specific sections)
  4. Reasons for detention at MTKDC (grouped sections)
  5. Reasons for detention at MTKDC (specific sections)

Tai Tam Gap Correctional Institution (TTGCI or TTG)

  1. Yearly admittances into TTGCI NEW
  2. Average daily detainee population at TTGCI
  3. End of month population at TTGCI

Tuen Mun Children & Juvenile Home (TMCJH)

  1. End of year population (2011-2020) at Tuen Mun Children and Juvenile Home (TMCJH)
  2. Yearly admittances into TMCJH

Nei Kwu Correctional Institution (NKCI)

  1. Yearly admittances into NKCI NEW
  2. Average daily detainee population at NKCI NEW
  3. End of month population at NKCI NEW

Section 2: Detention conditions

  1. Strip searches conducted by ImmD
  2. Strip searches by location
  3. Complaints filed against Immigration Department in relation to immigration detention
  4. Complaints related to immigration detention by institution that received the complaint
  5. Total complaints filed against Immigration Department
  6. Physical confrontations at CIC by type
  7. Physical confrontations at CIC relative to yearly admissions
  8. Injuries from physical confrontations at CIC
  9. Detainees receiving disciplinary penalties as a result of involvement in physical confrontations at CIC
  10. Physical confrontations at MTKDC
  11. Emergency ambulances sent to immigration detention facilities (CIC, MTKDC, TTG)
  12. Emergency ambulances sent to immigration detention facilities (CIC, MTKDC, TTG) broken down by type of emergency
  13. Number of outside escorts to public hospitals for CIC detainees (yearly) NEW
  14. Justices of the Peace visits to CIC and MTKDC
  15. Complaints and requests made to JPS, suggestions made by JPs by category

Section 3: Immigration Department enforcement actions

  1. ImmD Enforcement Actions Yearly
  2. Number of non-ethnic Chinese persons removed
  3. Immigration Offence Arrests
  4. Convictions of immigration offenders

Section 4: Refugees / Non-refoulement / Unified Screening Mechanism (USM) claims

  1. Number of non-refoulement claims by status of claim
  2. All substantiated USM claimants by nationality
  3. Demographics of claimants with outstanding USM claims at Sept 2021
  4. Number of Substantiations at TCAB
  5. Applications to work by USM claimants 

Section 1: Immigration detention numbers and demographics

Where are people detained?

Facilities managed by the Immigration Department, Correctional Services Department, and more.

In fact, the Immigration Ordinance states immigration detainees can be held in essentially any police, immigration, prison facility as well as border control points.

The two main detention facilities managed by the Immigration Department are Castle Peak Bay Immigration Centre (CIC) and Ma Tau Kok Detention Centre (MTKDC). As of early 2021, a third detention facility is in use. The former prison Tai Tam Gap Correctional Institution (TTGI) was recommissioned as an immigration detention facility. It is run by the Correctional Services Department instead of the Immigration Department and detainees are subject to the Prison Rules.

How many people are detained yearly?

The number of detention cases may not equal the sum of yearly admittances into CIC and MTK because 1) one person can be admitted into more than one institution (ex. Admitted to MTK then transferred to CIC) and 2) there are detention facilities other than CIC and MTK. In this regard, the ‘number of detention cases’ is currently seen as the most relevant number in answering the question ‘How many people are detained for immigration purposes every year in Hong Kong?’.

How many people are admitted to CIC and MTKDC every year?

Usage note: Please note the measurement units used. For example, yearly admissions and average daily population cannot be combined across time periods as they are different measurement units.

How many persons are released from CIC every year?

Where are the detainees in CIC from?

This chart shows the most common nationalities of detainees in CIC on Dec 31 of the past three years, with less common nationalities in “Other”.

The following chart shows all nationalities in detail on Dec 31 for a larger time period. 

Usage note: “End of year” indicates the number of people on the last day of the year (ex. Dec 31, 2018). This means that the data shows the snapshot of the detainee population only on that day, and cannot be generalized to represent the whole year. 

How old are the detainees in CIC?

This data shows a snapshot of the age groups in CIC on Dec 31, and thus cannot be generalized to represent the whole year.

This data shows a snapshot of the age groups in CIC on the end date of each month, and thus cannot be generalized to represent the whole year.

What is the gender of detainees at CIC?

Click on the items in the legend to filter out different categories.

This graph shows yearly admissions into CIC by gender. Data prior to 2020 is not maintained. The Immigration Department has stated that admissions data of transgender persons was not maintained.

What are the immigration statuses of detainees at CIC?

This data shows a snapshot of the age groups in CIC on the end date. ofeach month, and thus cannot be generalized to represent the whole year.

What are the nationalities of detainees in CIC and MTKDC?

This shows nationalities as a breakdown of yearly admittances to CIC and MTKDC, ie. the total number of people who enter the specified institution in a given year / time period.

Is there a recent snapshot of detainee demographic data?

These visualizations show demographic data of detainees who were at CIC on July 31, 2021. Click on the arrows to navigate to nationality, age, sex, and immigration status.

Who was detained at CIC in 2021?

These graphs show demographic data of detainees who were at CIC on the end of each month of 2021. Click on the arrows to navigate to nationality, age, sex, and immigration status.

Vocabulary List

Commonly Used Abbreviations

CIC – Castle Peak Bay Immigration Centre

CIU – Complaints Investigation Unit (of the Correctional Services Department)

CSD – Correctional Services Department

HKPF – Hong Kong Police Force

ImmD – Immigration Department

MTKDC – Ma Tau Kok Detention Centre

NKCI – Nei Kwu Correctional Institution

TTG / TTGCI – Tai Tam Gap Correctional Institution

Have questions, comments, suggestions? Please feel free to contact us through this contact form.