El Mencho, known as Nemesio Oseguera Cervantes, is the founder and supreme leader of the Jalisco New Generation Cartel (CJNG). He has expanded his criminal enterprise beyond drug trafficking, establishing powerful networks capable of assassinating judges, politicians, and military personnel across Mexico. His operations have had a significant impact on the criminal landscape of the country, drawing attention from law enforcement agencies both domestically and internationally.

Initially captured in the early 1990s with marijuana, El Mencho's rise in the criminal underworld saw him selling heroin to undercover police officers in San Francisco. Despite multiple arrests and deportations back to Mexico, he consistently managed to return to the United States until he ultimately decided to remain in Mexico, where he built a reputation as a formidable criminal leader. The low-profile nature of his operations, combined with a calculated approach to expanding his influence, has allowed him to remain elusive from authorities.

El Mencho's legacy as a key player in organized crime highlights a broader issue of violence and corruption in Mexico. His cartel has become known not only for drug trafficking but also for engaging in violent acts against officials and rival cartels. The implications of his power extend beyond criminal activity; they affect the safety and security of Mexican citizens, raising questions about governance and the effectiveness of efforts to combat such entrenched criminal organizations.