From [HERE] When Chinese police detained American professional basketball player Jeff Harper in Shenzhen last year, they didn’t formally arrest him, he says, but instead kept him locked in a room with a rancid mattress and a plastic chair for eight months.

That form of Chinese detention, called “residential surveillance in a designated location,” is used by authorities to hold a suspect for interrogation in a secret location before any arrest or charge. Human-rights groups describe it as a frightening situation that sometimes features violence and leaves the subject cut off from lawyers and family. Mr. Harper says he wasn’t physically abused but was tormented by the uncertainty around what authorities planned for him.

An unaffiliated basketball pro who had played in 12 countries, Mr. Harper had been in Shenzhen for five days for a tournament when he was detained after an altercation he says he was later told led to a man’s death. He was eventually released and permitted to leave China in September 2020 without ever being charged with any crime or appearing in court.

The residential-surveillance system has received international attention because of a number of high-profile cases involving political opponents of Beijing’s leadership and sometimes foreigners such as Mr. Harper.

The benign term “residential surveillance” denotes the system’s origins as a type of house arrest. But accounts by detainees and findings by human-rights groups suggest it may be a more systematized process that can feature purpose-built jail-like facilities with dedicated staff, sometimes referred to as black jails. Mr. Harper says he was held in what appeared to be a residential building for police officers.

According to research by a team of human-rights groups led by Madrid-based Safeguard Defenders, a nonprofit focused on human rights in China, some 5,810 cases of residential surveillance were recorded in open-source Chinese court records for 2020, up 91% from the year before. The group, which has tracked rising mentions of the practice in nine years worth of court records, estimates the use of residential surveillance is closer to double that or more.

“This is used at a mass level,” says Peter Dahlin, director of Safeguard Defenders, who in the past ran a legal-aid nonprofit in China before being detained in 2016 and deported. State media at the time accused him of endangering state security by funding Chinese human-rights lawyers. Safeguard Defenders, founded after he left China, has submitted its findings to human-rights bodies at the United Nations that have criticized China’s residential-surveillance practices. [MORE]