This clause came from the era of Al Capone, who famously boasted, "They can't collect legal taxes from illegal money." (Which was true at the time.) They added

This clause came from the era of Al Capone, who famously boasted, "They can't collect legal taxes from illegal money." (Which was true at the time.) They added this clause and then ended up catching Capone for tax evasion. https://www.forbes.com/sites/kellyphillipserb/2020/10/17/al-capone-convicted-on-this-day-in-1931-after-boasting-they-cant-collect-legal-taxes-from-illegal-money/?sh=32d97b381435 https://www.forbes.com/sites/kellyphillipserb/2020/10/17/al-...