The “normal case”: Fewer than 50,000 – 500,000 images

Police officers handle great volumes of data and large numbers of images and videos in investigations of child sexual abuse material. There are many theories about the number of images cases comprise of and to what extent the crime is increasing. To get a better overview, in this report we separate the total amount of images that a case comprises of from the number of images that contain child sexual abuse. The report also considers what an ‘average’ case is.

Verified numbers – Taskforce Argos

To verify the numbers provided by this year’s survey, we also looked at the numbers involved in a specific operation consisting of close to a 100 seizures, led by Taskforce Argos* in Australia.

* Task Force Argos, Queensland Police, Australia, is a specialist unit responsible for the investigation of online child exploitation and abuse. Approximately 40 people work at Taskforce Argos.

How many images does the average case contain?

The police officers surveyed reported that the number of image-files that they handle in an average case can be anywhere between 50,000 images to five million images. This includes images that do not contain child sexual abuse. Hence, the estimate varies greatly. However, the majority of respondents pointed to fewer than 50,000 images or 100,000-500,000 images. Taskforce Argos numbers shows that a case on average contains 125,000 images.

90 percent of police officers reported that the number of images that actually contain child sexual abuse in an average case is fewer than 50,000, and more than half say that the average case contains fewer than ten hours of video. Taskforce Argos corroborates these numbers saying that their average investigation contains 25,000-30,000 images and 700-900 files with filmed child sexual abuse material.

“Fewer than ten hours of film” and “700-900 files of material” might be viewed as widely different, however as films showing child sexual abuse generally are very short, these two measurements indicate a similar amount of content.

Statistics shared by Taskforce Argos

Number of investigations:
91 seizures, all from the same police operation. Each case represents one suspect.

Total amount of material in the investigation:
60.4 TB. Biggest case in the investigation: 5.1 TB

Total amount of CSAM in the investigation:
12.1-15.1 TB (estimate based on the fact that normally 75-80 % of material in an investigation does not contain CSAM).

”The Average case”
Based on these numbers an “average case” would look like this: In total almost 700 GB data or 500,000 files. Of these 125,000 files will be images and 3,600 videos. The case would contain 140-170 Gigabytes CSAM, ca 25,000-30,000 images and 700-900 videos.

The biggest cases

The very biggest cases are enormous with up to 100 Terabytes (TB) of material or 100 million images in total and 30 TB of material or 10 million images showing child sexual abuse content. The numbers shared by Taskforce Argos are not of that magnitude, but highlight that cases can be different in terms of how much relevant material they include. One case they worked on contained almost six million images, whereof “only” 24,000 images showed child sexual abuse. Another case contained 3,5 million images of which more than 2,3 million turned out to contain child sexual abuse, most of it previously not known to the police.

Statistics shared by Taskforce Argos
Two examples showing that cases can be very different:

Case 1:
5 930, 915 images. 413,355 previously unknown images to the police, which needed reviewing. 24,431 contained CSAM.

Case 2:
3 552,994 images. 2 580,360 previously unknown images to the police, which needed reviewing. 2 353, 550 contained CSAM.

20,000 images is a considerable amount

The overall picture shows that even though the biggest investigations are abnormally large, most cases are nowhere near that big. Still, 100,000 images is a huge number to scrutinise, and 5,000, 20,000 and 30,000 images is a considerable amount of child sexual abuse material to possess.

COMMENT ON INSIGHT 2

“It shouldn’t be a numbers game”

Taskforce Argos, Queensland Police, Australien: Adèle Desirs, Jon Rouse, Paul Griffiths, Scott Ballantyne och Stuart Butler.

READ COMMENT

“In our experience, cases are not growing exponentially bigger. We seize bigger hard drives, but they are normally not full. The average case is probably around 200 000-300 000 images, where about 80 percent can be ignored. This has not changed over the last number of years.”

More insights from the report

DEVELOPMENT OF TECHNOLOGY – BOTH A CHALLENGE AND AN OPPORTUNITY

THE “NORMAL CASE”: FEWER THAN 50,000–500,000 IMAGES

THERE IS NO SUCH THING AS A TYPICAL OFFENDER (Consumer of child sexual abuse material)

THERE IS A CORRELATION BETWEEN VIEWING CHILD SEXUAL ABUSE MATERIAL AND ABUSING CHILDREN

THE OFFENDER IS MOST LIKELY TO VICTIMISE CLOSE FAMILY MEMBERS OR RELATIVES

CSAM IS VIEWED 24-HOURS A DAY, THROUGHOUT THE WEEK – INCLUDING HOURS SPENT IN THE WORK PLACE

TRENDS: THE USE OF CHATROOMS AND APPS IS INCREASING

TRENDS: THE USE OF ANONYMISATION TECHNOLOGIES, ENCRYPTION AND CLOUD STORAGE IS INCREASING

THOUGHTS ON THE REPORT

“To eradicate child sexual abuse we need more resources, and, most importantly, they need to be applied in the right way.”