The Story of People Who Tried to Smuggle QR Codes into Prisons
The Method of Printing QR Codes on Letters
Letters delivered to prison inmates are censored by corrections officers. They read through each letter one by one to check whether it contains dangerous items or instructions for an escape. However, just by looking, they cannot tell the "contents" of a QR code printed on a letter.
In several U.S. states, attempts to print QR codes on letters addressed to inmates to give them access to outside websites have been reported. The destinations of these QR codes sometimes included means of contacting criminal organizations, information on illegal drug deals, and threatening messages to witnesses.
In response to this problem, some prisons have introduced a rule that "letters containing QR codes will be refused." The number of facilities adopting a method of scanning letters and giving inmates only a digital copy (while keeping the original) is also increasing. With a digital copy, it is not possible to scan the QR code.
Inmates Who Got QR Code Tattoos
There are people outside prisons as well who get QR code tattoos on their bodies (as fashion or self-expression). However, cases of QR code tattoos being done inside prisons drew attention as a security concern.
In theory, a QR code tattoo can contain a URL or text information. If a visitor scanned the tattoo with a smartphone, it could become a secret means of communication with the outside. Simply by telling a visitor "scan the QR code on my arm," an inmate could accurately pass on a long URL or message that is hard to convey verbally.
However, in reality, QR code tattoos often blur over time and become unreadable (due to the stretching and shrinking of the skin and the spreading of pigment), and they are considered to have low reliability as a practical means of communication. Even so, for prison security staff, they are a target of vigilance as an "unexpected loophole."
QR Codes Hidden in Books and Magazines Sent to Inmates
Books and magazines that are permitted to be sent into prisons may also contain QR codes. QR codes officially printed by publishers (links to the author's site, links to related videos, and so on) are harmless by nature.
However, attempts to stick small QR code stickers on the pages of books sent to inmates to use them as a means of communication with the outside have been reported. Finding a small QR code sticker among the hundreds of pages in a book is a heavy burden for those doing the censoring.
As a countermeasure, some prisons have introduced a rule that books sent to inmates must be shipped directly from the publisher (items sent in by individuals are prohibited). This is because a book that arrives directly from the publisher carries no risk of a QR code sticker being attached along the way.
There Are Also Cases Where Prisons "Make Use of" QR Codes
While prisons are wary of QR codes as something "brought in," cases of prisons themselves making use of QR codes are also increasing.
Inmate identification: QR codes are printed on inmates' ID cards to manage movement within the facility and the distribution of meals. Because a QR code can store more information than a barcode, the name, inmate number, allergy information, medical information, and so on can be combined into a single QR code.
Facility equipment management: QR codes are attached to equipment such as beds, blankets, and tableware to digitize inventory management and distribution records.
Educational programs: A system in which QR codes are printed on materials for rehabilitation programs, and scanning them with a tablet displays learning content. It is a positive example of using QR codes to support inmates' return to society.
QR Codes Are a "Neutral Tool"
The prison cases show once again that QR codes are a "neutral tool." Just as a knife can be used both for cooking and for crime, QR codes can be used both for legitimate and for illegitimate purposes. Technology itself has no good or evil, and its value is determined by the intentions of the people who use it.
Prison security staff know firsthand how great the "power to convey information" of the small square called a QR code is. Each of the QR codes we scan in daily life is also packed with various kinds of information, such as text, URLs, contact details, and Wi-Fi information. That ease of use and large amount of information are the strength of QR codes, and at the same time a security challenge.