Genaro García Luna was a man long spoken of with reverence.

He had an impressive career behind him: first in the secret service, then from 2001 as director of the Mexican federal investigation agency AFI and from 2006 to 2012 as Minister of Internal Security.

For years, García Luna had dedicated himself to fighting drug smuggling in Mexico.

As a minister at the age of 38, he ended up spearheading the “war on drugs” launched by then-President Felipe Calderón, which cost thousands of lives.

But all the deeper was García Luna's public case.

The 2020 indictment against the Mexican man said he had "betrayed those he swore to protect" for over two decades.

He is now on trial in Brooklyn, New York.

The former top drug fighter in Mexico is said to have worked with the Sinaloa cartel, accepted millions of dollars in bribes and helped smuggle dozens of tons of cocaine into the United States.

How deep García Luna was in the cartel's drug business became clear on the first day of the court hearing on Monday.

Sergio Villarreal Barragán, aka "El Grande", the Great, sat on the witness stand.

He was part of the now-defunct Beltrán Leyva Cartel, which worked closely with the Sinaloa Cartel, was arrested in 2010 and extradited to the United States in 2012.

Villarreal Barragán described how a rival cartel's shipment of cocaine was intercepted in the early 2000s.

After the drugs had been taken to a warehouse, his boss appeared there accompanied by Genaro García Luna, then director of the federal investigation agency.

The deal: half of the profits from the two tons of cocaine would go to the cartel, the other half to their protégé,

The prosecutor describes the double life of the prosecutor

In his opening statement, prosecutor Philip Pilmar highlighted García Luna's double life since 2001.

Actually, he was entrusted with working for the Mexican people.

But "he had a second job, a dirtier one," Pilmar said.

He accepted millions of dollars in cash bribes "so Mexico's largest drug cartel could ship tons of cocaine to the United States."

According to prosecutors, under García Luna, federal police officers unloaded cocaine at the Mexico City airport and served as armed mercenaries in the fight against enemies of the Sinaloa cartel.

García Luna is the highest-ranking Mexican official ever tried in America.

After retiring from politics in 2012, the Mexican moved to Florida and founded a security company there.

He was arrested in Texas in 2019 and has been in custody ever since.

The trial is taking place in the same court as that of Mexican drug lord Joaquin "El Chapo" Guzmán.

The head of the Sinaloa cartel was sentenced to life imprisonment there in 2019 for drug trafficking and money laundering, among other things - by judge Brian Cogan, who also presides over García Luna's trial.

The defense paints a picture of an honest man

However, García Luna's defense portrays her client as the man he was long thought to be: an honest official who helped the United States arrest leaders of the Sinaloa cartel.

There is no credible evidence that he helped the drug smugglers.

Years ago, García Luna brushed aside allegations of bribery by journalists and arrested cartel members.

In New York, the defense said the charges were based on "rumors, speculation and the testimonies of the worst criminals in the world".

They wanted revenge on García Luna because he had been involved in their arrests.

A total of twelve witnesses from the milieu are to testify in the trial against García Luna.

A former Sinaloa member had already made serious allegations against García Luna in the "El Chapo" trial.

Jesús Zambada García said he met him twice in a restaurant when he was minister and both times handed him a bag containing $3 million in cash.

In return, García Luna made sure the drug shipments went unmolested and provided the cartel with information about ongoing investigations and rival groups.

For the United States, the trial against García Luna also means dealing with possible mistakes in its own ranks.

At the time, the DEA was working closely with García Luna, and photos show him with then-Secretary of State Hillary Clinton and President Barack Obama – the defense sees such documents as evidence of his integrity.