In July 2007, Landín Martínez was arrested after being spotted by an off-duty U.S. Drug Enforcement Administration (DEA) agent inside a supermarket in McAllen, Texas.

[3] In March 1997, the Attorney General's Office (PGR) arrested him and Pablo Villanueva Hernández, another police chief, for reportedly being involved with Los Nichos, a Reynosa-based drug gang.

In Mexico, he ran a criminal organization responsible for international drug trafficking; in the U.S., he spent time with his family, including his three children and four grandchildren.

[9] U.S. authorities tracked Landín Martínez's drug trafficking activities back to 1998, when his criminal cells in Granjeno and Peñitas, Texas, worked with a family-led smuggling ring headed by Francisco Meza-Rojas, a former McAllen police officer.

[3][10] Once drug cells were finalized, couriers would bring the money back to Mexico from all over the U.S. through the Reynosa border crossing, where it reached Landín Martínez's network.

[8] The Reynosa corridor was headed by Gregorio Sauceda Gamboa, a kingpin that reported to Osiel Cárdenas Guillén, the top leader of the cartel.

[15][16] However, Sauceda Gamboa began having differences with the Gulf Cartel's leadership due to his perceived weakness;[17][18] his excessive drinking, drug addiction, and cancer diagnosis pushed him to the sidelines.

[18] The leadership differences triggered an internal rift in the Gulf Cartel; multiple regional leaders were killed, and Landín Martínez was rumored dead in 2006.

[23] In addition to Landín Martínez, the DEA's investigation also focused on arresting ten high-ranking members of the Gulf Cartel and Los Zetas, who were placed in a most-wanted list with bounties.

[25] On 17 July 2007, Landín Martínez was spotted inside a H-E-B supermarket in McAllen, Texas, by off-duty DEA agent Leonardo Silva.

His attorney, Oscar Rodolfo Alvarez, told the judge that Landín Martínez fled Mexico and sought for safe haven in the U.S. because he feared for his life.

Parking lots close to the courthouse were cordoned off by the police, and officers screened over 30 of Landín Martínez's family members who attended the initial proceedings.

The SWAT team of the Hidalgo County Sheriff's Office was on standby that evening by the McAllen Police Department, where Landín Martínez was planned to be held for the duration of the trial.

[36] On 15 January, witness Francisco Camacho Barajas told the jury that Landín Martínez was involved in the Gulf Cartel in Reynosa while still working for the Tamaulipas State Police.

They cited his drug abuse and lack of first-hand knowledge of Landín Martínez's supposed involvement in the Gulf Cartel as evidence of his unreliability as a witness.

[36] Landín Martínez and Robledo were present while recordings of phone calls, intercepted by the prosecution's witness Ricardo Muñiz, were played for the jury.

[38] The recordings included mentions of aliases of members within the Gulf Cartel, drug and money operations, and of worries that they may be heard from authorities through wiretapping.

One of the phones calls from 2006 mentioned a man known by his alias "Maestro" (English: Teacher), who was responsible for smuggling money from the U.S. to Mexico for Landín Martínez.

Several U.S. law enforcement agents who participated in drug seizures from Muñiz's operations were expected to testify against Landín Martínez and Robledo that afternoon before the court session ended.

Daniel Zamorano Marchant, one of the witnesses who had previously smuggled marijuana and methamphetamine for the Gulf Cartel, stated that Landín Martínez collected fees from drug and human traffickers who wanted to operate in his turf.

Another witness, Antonio Parra Sáenz, took the stance and said he was kidnapped by the Gulf Cartel in Reynosa and tortured for 15 days after the Mexican police seized US$2.5 million in cocaine from a stash house he was guarding in Las Milpas, Texas.

[25][40] The seizure was conducted in July 2006, and resulted in the confiscation of 520 lb (240 kg) of cocaine, about 2 oz (57 g) of methamphetamine, US$40,000 in cash, and firearms, ammunition and bullet proof vests.

[41] On 18 January, Arturo Alonso Sequera, a drug smuggler from North Carolina that worked for the Gulf Cartel under Landín Martínez, testified against him in court.

[42] During the seven-day trial,[43] the jury reviewed the exhibits presented by the prosecution, which included drug seizure samples and hours of wiretapped conversations between Landín Martínez's smugglers in the Rio Grande Valley.

[48] On 22 January, after nearly eight and a half hours in deliberations that spanned for over two days,[43] Landín Martínez was found guilty of all charges: ten counts of drug trafficking, conspiracy, and money laundering.

U.S. authorities also stated that the conviction of Landín Martínez would likely serve as a stepping-stone for the case against Cárdenas Guillén, the top leader of the Gulf Cartel who was extradited to the U.S. in 2007.

He was handed life imprisonment for being accountable for the possession with intent to distribute of 150 kg (330 lb) of cocaine and for his leadership role in the Gulf Cartel.

In addition to these convictions, Landín Martínez also received the maximum sentence of 20 years for money laundering, which included drug proceeds over US$1.6 million.

The testimony presented in the trial proved that Landín Martínez exercised the use of force to control drug trafficking activities in Reynosa and against other members of the Gulf Cartel.

Landín Martínez's defense team said they were surprised when they first heard that U.S. authorities wanted to keep his jewelry, especially after they returned his watch, wallet, and rings prior to the start of his trial.