Exclusive Brethren used Thompson and Clark to spy on former members 19 Apr, 2021 08:33 PM 14 minutes to read A generic photo of a man in his car doing surveillance with a camera. Photo / 123rf A generic photo of a man in his car doing surveillance with a camera. Photo / 123rf RNZ The Exclusive Brethren church has been using the controversial private investigators Thompson and Clark to spy on former members of the church. Over the past two years, Thompson and Clark has conducted hundreds of hours of surveillance on former members who have criticised the cult-like church. The private investigators have watched ex-Brethren from cars and parked surveillance vans and have taken photographs of people entering and leaving their homes.