Elvin Mustafayev is a board member of the Confederation of Trade Unions Table of Workers. He also worked as a courier. He was initially targeted after participating in an August 2023 protest of couriers. The protesters expressed dissatisfaction with the seizure of their scooters after authorities introduced new traffic rules. 

The Narimanov District Police Department detained Mustafayev on August 4, 2023, under charges of large-scale drug trafficking. The police accused him of illegally acquiring and possessing heroin. The investigation failed to indicate the source where Mustafayev purchased the drugs. On August 5, 2023, the Binagadi District Court of Baku City remanded Mustafayev for four months of pre-trial detention.

On January 31, 2024, the Baku Court for Serious Crimes sentenced Mustafayev to three years in prison. The court found Mustafayev not guilty on the charges related to illegal sale of drugs, which holds a sentence of five to twelve years in jail. The court reclassified the initial charges under the more lenient Criminal Code Article 234.1-1 (illegal acquisition, storage, production, processing, and transportation of narcotic drugs without intent to sell).