When the Colombian drug lord Daniel Barrera was arrested in 2012 in an unusual takedown that involved the United States, British, Colombian and Venezuelan authorities, Colombia’s president, Juan Manuel Santos, called him “the last of the great kingpins.”
Mr. Barrera, known as El Loco, was extradited from Colombia to the United States in 2013 and pleaded guilty to charges brought against him in federal courts in Brooklyn, Miami and Manhattan.
Now, as he faces sentencing on Monday in Manhattan, where his cases were consolidated, Mr. Barrera, who is in his late 40s, could receive life in prison. But his lawyer, seeking leniency, has filed a court brief detailing Mr. Barrera’s efforts to surrender to the United States and offer his cooperation before he was ever arrested. A redacted version of the brief was filed on Sunday.
The lawyer, Ruben Oliva, in a memo submitted to Judge Gregory H. Woods of Federal District Court, said that in the year before the arrest, Mr. Barrera instructed his lawyers to begin negotiating with the United States for his voluntary surrender and cooperation, and he was already actively encouraging many of his associates to turn themselves in.
Mr. Barrera also directly assisted in the surrender and cooperation of two of his associates, Mr. Oliva wrote. After he arrived in the United States, Mr. Barrera “provided extensive written proffers in an effort to obtain a cooperation agreement,” Mr. Olivia added.
Mr. Oliva said that his client’s offers were ultimately rejected, which he suggested was because of “political intervention by Colombia.”
It was not clear how or whether the office of Preet Bharara, the United States attorney in Manhattan, addressed Mr. Oliva’s claims; major portions of its sentencing brief have been redacted from public view. Mr. Bharara’s office declined to comment, as did the Drug Enforcement Administration. The Colombian Embassy in Washington did not respond to a request for comment. Mr. Oliva also declined to comment.
Mr. Bharara’s office said in its brief that until his arrest, Mr. Barrera “was one of Colombia’s most notorious, prolific and violent drug traffickers.”
From 1998 until 2010, prosecutors said, Mr. Barrera ran a cocaine manufacturing and trafficking syndicate that shipped cocaine powder to locations on four continents, including to the United States. The organization bought raw cocaine base or paste from a Colombian terrorist group known as the Revolutionary Armed Forces of Colombia, or the FARC, and converted it into powder at laboratories Mr. Barrera ran in an area controlled by another terrorist group, the United Self-Defense Forces of Colombia, or the A.U.C. In return for payments, prosecutors said, the A.U.C. allowed Mr. Barrera to move the drugs out of the country.
Mr. Barrera’s organization produced hundreds of tons of cocaine annually, prosecutors said, earning him tens of millions of dollars in profits.
“The sheer amount of cocaine for which Barrera is responsible,” prosecutors wrote, “sets Barrera apart from other drug traffickers.” He also traded cocaine for about 800 to 1,000 AK47 assault rifles and “murdered numerous individuals,” the government said.
But Mr. Oliva, in his memo, offers a contrasting view. In 2010, he said, Mr. Barrera declared — apparently to associates — that he would “initiate negotiations with the United States government and surrender.” He urged them to do the same. Much of the next three pages is redacted. The memo then says Mr. Barrera hired Mr. Oliva “for the purpose of negotiating his surrender.”
“Mr. Barrera’s efforts were ignored,” Mr. Oliva wrote, adding, “These efforts were met by the government with stonewalling, indifference and intransigence.”
Mr. Oliva has not specified what sentence he is seeking. But in his memo, he asked Judge Woods to take into account Mr. Barrera’s unsuccessful efforts at cooperation, as well as Mr. Barrera’s decision not to contest extradition and to plead guilty. Prosecutors said in their memo that a 35-year sentence would be appropriate. They said the United States had made assurances to Colombia that it would not seek a life sentence.