December 20th, 2018, US President Donald Trump signed the 2018 Farm Bill. The 2018 Farm Bill is seen by many as a revolutionary piece of legislature for the hemp industry. For decades, hemp (cannabis sativa) has been listed as a Controlled Substance, putting it alongside marijuana and other intoxicating substances. However, as of the 2018 Farm Bill signing, growing hemp in the United States is no longer illegal will be placed under the supervision of the Department of Agriculture.
The Marihuana Tax Act of 1937 was one of the first steps that America made in the crackdown on hemp plants. However, even before this was passed, attempts to slow down the hemp industry took place as early as 1906. Back then, hemp was used primarily as a way to make paper.
The Tax Act of 1937 was eventually overruled by Leary v. United States in 1969. This found the previously enacted tax act unconstitutional, after Timothy Leary himself was arrested for possession of marijuana.
In the next year, the Controlled Substances Act was passed, which the new 2018 Farm Bill successfully overrules. This was a replacement for the Marihuana Tax Act of 1937 and placed hemp as a controlled substance.