The Board of Immigration Appeals (BIA) has determined that a conviction for solicitation to possess marijuana for sale is a crime involving moral turpitude, rendering a person inadmissible. The BIA noted that the inadmissibility provision for crimes involving moral turpitude reference only attempts and conspiracies to commit crimes involving moral turpitude, and not solicitation to commit such crimes, but remained unpersuaded that Congress intended to exclude solicitation offenses from the provision.
The full text of Matter of Gonzalez Romo can be found here: https://www.justice.gov/eoir/file/852311/download