Not to be argumentative, but it's worth noting that Lynchings were considered legal because there was usually a criminal accusation and local officials involved.[1] A bill has been introduced in every Congress since 1918 to make Lynching illegal. It actually became illegal with the Emmett Till Antilynching Act (H.R. 55), enacted on March 29, 2022[2].

Now it's true that it could have been prosecuted anyway as murder or a civil rights violation, but it wasn't because of that convenient interpretation.

1. https://naacp.org/find-resources/history-explained/history-l...

2. https://www.congress.gov/bill/117th-congress/house-bill/55