Official reports and spending documents on on a controversial surveillance technology show that in the past year, UK police have deemed the testing of a system that can collect people’s “internet connection records” a success, and have started work to potentially introduce the system nationally. Critics say the system is highly intrusive, and that officials have a history of not properly protecting people’s data. Much of the technology and its operation is shrouded in secrecy, with bodies refusing to answer questions about the systems.