The convicted mastermind behind the world's largest online narcotics emporium wrote a heartfelt letter to the judge who, on Friday, will decide whether or not he spends the rest of his life in prison.

Silk Road founder Ross Ulbricht, 31, and 97 of his friends and relatives wrote letters to District Judge Katherine Forrest pleading for the most lenient sentence possible — in this case, 20 years.

Ulbricht's own letter, which is just over a page long, is significant given his decision not to testify during the trial. It is his first attempt to defend — and show remorse for — his actions.

"When I created Silk Road I wasn't seeking financial gain," he writes. "I created Silk Road because ... I believed at the time that people should have the right to buy and sell whatever they wanted so long as they weren't hurting anyone else."

Throughout the trial, the prosecution, led by Assistant US Attorneys Serrin Turner and Timothy Howard, attempted to characterize Ulbricht as a ruthless drug kingpin who was "motivated by greed and vanity," and whose website resulted in countless addictions and multiple drug-related deaths because of the ease with which it allowed people to purchase drugs.

"It does not matter that Ulbricht did not specifically intend any deaths to occur from his conduct," the prosecution writes in its sentencing memorandum. "Ulbricht was well aware of the dangers inherent in the products he was selling."

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Ulbricht partially concedes this point in his letter.

"Silk Road was supposed to be about giving people the freedom to make their own choices, to pursue their own happiness," he writes. "While I still don't think people should be denied this right, I never sought to create a site that would provide another avenue for people to feed their addictions."

Ulbricht's lawyer, Joshua Dratel, argued that Silk Road had provided a platform for buying and selling drugs that was "far safer" than traditional drug dealing on the street.

In the defense's sentencing memorandum, Dratel notes how Ulbricht was an Eagle Scout and "excelled in school," and has "a unique set of skills and traits that will enable him to become a valuable asset to his community."

"In creating Silk Road ... I squandered the enviable upbringing my family provided me, all of the opportunities I have been given, and the ones I have earned, and my talents," Ulbricht writes. "I could have done so much more with my life."

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Some of Ulbricht's fellow inmates also wrote letters of support on his behalf.

"We shared a cell at MDC and spent 24 hours, 7 days a week together for several months," writes inmate Michael Satterfield. "During that time, Ross ... spent his days sharing positive thoughts with the other inmates ... and began teaching yoga and meditation to the general population, inviting anyone to join in."

Ulbricht also tutored fellow inmates in math and physics while helping others study for their GED, according to another inmate, Davit Mirzoyan.

"I will not lose my love for humanity during my years of imprisonment," Ulbricht writes in his letter.

Still, the prosecution has insisted that Ulbricht's personal traits are not significant mitigating factors, arguing that the now-31-year-old "cultivated a darker side of his personality ... one that his friends and family would have found shocking."