Not knowledge, just random thoughts: Could they return "We can not give you that information because it is a matter of national security." (Although that's still a sign that they have info on you that they gathered from Big Tech). Or they could give you pages and pages covered with black rectangles from margin to margin.
The scary thing is, they wouldn't have done any manual listening/monitoring, all the data can just be fed into some big data computer[1] and it spits out your "threat index".
For a Black Mirror episode plot, the main character hangs out every Friday at a pizza place that Google Maps has mislabeled as a mosque. The "AI" misclassifies his watch on a recent Instagram photo as the Casio F-91W, he gets detained as he tries to reenter the country, with the FBI agents not knowing why he's a baddie other than the fact that the computer flagged him after his threat index jumped over a threshold.
[1] e.g. from the NSA whisteblower: https://en.wikipedia.org/wiki/ThinThread: "Hayden admitted that the analysis technology is the underlying basis of current NSA analysis techniques"