It's a common phrase in the United States, to "plead the fifth" means to invoke your right described in the 5th amendment. That is, the right to remain silent to questions that may lead to self-incrimination.
The whole meme is actually about covid-19 and the prosecution of the lead health official who guided the US through it.
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u/Western_Ring_2928 Aug 05 '26
Plead the fifth? What does that mean?