Mugshots end up online because arrest records are public, and automated...

https://www.scribd.com/document/1016662258/If-My-Case-Was-Dismissed-What-Proof-Helps-With-Mugshot-Removal-227158

Mugshots end up online because arrest records are public, and automated scrapers constantly pull this data to populate third-party sites. Once posted, these images multiply rapidly across search results