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It would be highly unusual to see that affidavit now, let alone at any point before someone is formally charged, said Sarah Krissoff, a former federal prosecutor in New York now in private practice.
“If there are sources close to Trump who are providing that information, the department is going to be very careful about outing those sources,” she said.
Christopher Slobogin, director of the Criminal Justice Program at Vanderbilt University, said that while the affidavit should eventually become public, the government “wouldn’t want to tip its hand too early” about the details of its probe. Prosecutors may want to keep information in the application secret until they present a case to a grand jury for a possible indictment, he said.
Information in the affidavit about what they learned from a source at Mar-a-Lago could expose the person even if their name is redacted, Slobogin said.
“The application should describe in a fair amount of detail how the informant came by the information, the basis of the informant’s information, and indicia of reliability -- why we can trust this informant,” Slobogin said. “There’s a lot of detail in a good warrant application that would help someone identify an informant.”
https://www.bloomberg.com/news/arti...-why-mar-a-lago-affidavit-remains-under-wraps