Years ago I worked at a place where I was bound by the Official Secrets Act and breaking the rules could mean 5 years’ imprisonment, so this may apply to your son. I then worked at an extremely secretive government agency where I spent the last 15 years before I retired, and they were the most exciting years of my working life.
At both places I transcribed LD product from homes, cars and outdoor locations. The work was indescribably hard as there was invariably background noise. If it was critically important, e.g. catching a person's name, can you imagine listening to one sentence over and over even if it took several hours? LD product can be the greatest invasion of privacy you could ever imagine and can be disgusting and extremely shocking.
LE agencies, whether the police or other agencies, have to produce a detailed sworn affidavit to a judge setting out the reasons why an LD is necessary. If the application is granted, he will issue a warrant authorising the use of the device.
Prior to installing an LD, surveillance was carried out to establish if there was a pattern as to when the home was usually vacant or occupied. If no-one was home, investigators would then break and enter the premises. It was potentially dangerous as someone could turn up unexpectedly. I don’t know how they were able to access a home through a locked door or window but I’m guessing they must have used someone with lockpicking skills, but technology has advanced and things may be done differently now. I won’t disclose where devices were usually placed in homes and I never knew where they were placed in cars.
I hope this helps.
