William J. Brennan, Jr., Rogers v. Missouri Pacific Railroad Company…
“ The statute supplants that duty with the far more drastic duty of paying damages for injury or death at work due in whole or in part to the employer's negligence. The employer is stripped of his common-law defenses and for practical purposes the inquiry in these cases today rarely presents more than the single question whether negligence of the employer played any part, however small, in the injury or death which is the subject of the suit. ”
