Economy Trump vows to back law to protect marijuana industry Updated : April 14, 2018 12:48 PM IST It marked the latest flip by the president who pledged while he was campaigning to respect states that legalized marijuana . Marijuana has been fully legalized in eight states, and 24 states allow some form of marijuana use. Subscribe to Moneycontrol PRO at just Rs.33/- per month for the first year. Use code SUPERPRO. Limited period offer. Available on Web and Android.