according to the preamble what was the main concern of the knights of labor
Knights of Labor The Knights' primary demand was for an eight-hour day; they also called for legislation to end child and convict labor, as well as a graduated income tax. They were eager supporters of cooperatives. The only woman to hold office in the Knights of Labor, Leonora Barry worked as an investigator and described the horrific conditions in factories, conditions tantamount to the abuse of women and children. These reports made Barry the first person to collect national statistics on the American working woman.[7]
Child labor laws in the United States The common legal opinion on federal child labor regulation reversed in the 1930s. Congress passed the Fair Labor Standards Act in 1938 regulating the employment of those under 16 or 18 years of age, and the Supreme Court upheld the law.[6] After this shift, the amendment has been described as "moot"[7] and effectively part of the Constitution.[8]