I agree that it’s possibly a badly positioned rifle plate. The picture looks like it’s outdoors, so they may just hang that over his dressier body armor when his is potentially exposed to rifle fire.
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It’s indoors.
Walking through the Capitol.
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It’s Indoors, and he and Pelosi are guarded by SS.
The procession of other Congress Critters are separated and behind a gap after the rear detail.
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