Late in 2000, in Adelaide, Australia, a young woman was visited by a survey interviewer, doing a household survey. "Good afternoon, madam," said the interviewer when the woman answered the door. The interviewer was wearing an official looking badge, labelled Compass Research [not the real name] and Market Research Society of Australia.
"My name is Bertha Bluggs," she began [or whatever it was]. "I'm doing a survey for Compass Research, and we work according to the ethical standards of the Market Research Society. Now, I'd like to ask you some questions about your recent purchases of toiletries and bathroom products..."
The young woman answered the questions, but there were some answers she wasn't sure of. She let the interviewer go into her bathroom to check on the brand names she couldn't remember. The interview went smoothly, and the interviewer left.
"This is a good lurk," the young woman thought. A few days later, she made herself an impressive looking badge, travelled a few suburbs from her home, and knocked on a door. An older woman answered.
"I've come to inspect your toilet rolls," said the new interviewer, flashing her badge. "I'm doing this survey on behalf of Compass Research and the Market Research Society. Now let me in, please. I must see your bathroom."
The older woman was quite upset at this approach, and refused admission to her bathroom. The younger woman insisted. "This is an official survey," she said. The older woman was adamant. Eventually she called the police, who caught up with the "interviewer" at a nearby address. It seemed that she was planning some robbery, and saw this as a good excuse to check out the houses of likely victims.
The research company (not ours) and the Market Research Society were suitably appalled - but the only reason the approach didn't work is that the young woman hadn't been well enough trained. Any reasonably competent research interviewer could easily have gained permission to inspect those toilet rolls.