Interesting.
sur·vey
VERB
(of a person or their eyes) look carefully and thoroughly at (someone or something), especially so as to appraise them:
“her green eyes surveyed him coolly” · [more]
synonyms: look at · look over · observe · view · contemplate · regard · gaze at · [more]
investigate the opinions or experience of (a group of people) by asking them questions:
“95% of patients surveyed were satisfied with the health service”
investigate (behavior or opinions) by questioning a group of people:
“the investigator surveyed the attitudes and beliefs held by residents”
synonyms: interview · question · canvass · poll · cross-examine · investigate · [more]
Surveilled seems a better fit if the target is obtaining documents or tapes of conversations, but I suppose surveyed works, too, as it would be to study the subjects’ thought processes about the documents and conversations.
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Let’s go with Webster’s 1828 and forget the injection of illiteracy.
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