There is a form of avak loshon hara that can result from one’s regard for the laws of forbidden speech. If one says that he is reluctant to discuss a particular individual so as to avoid speaking loshon hara, he is, in effect, communicating that he knows something negative about that person.
“I’d rather not discuss So-and-so,” is a derogatory statement.
Sefer Chofetz Chaim, 6 Cheshvan, page 120
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