Attack the train conductor in Abilene and he'll slay you after a few rounds of combat, with an act indicating that you've been lynched by an angry mob for attacking him. You'll get this whois, and you'll get "the scoundrel" post-title, which seems to pretty easily get buried under all the other post-titles in the game. You won't be able to ride the trains anymore if you have this post-title active.
If you go to the judge in the courthouse, and ask him TRAIN he'll tell you that if you pay a fine, he'll issue a court order to the train companies to let you ride again. Pay the man 1000 dollars to take care of your fine, and he'll remove the post-title (but not the whois).
You can get the post-title again by getting slain again.