NEW YORK—"My addiction became very expensive, and I could no longer afford it," said Michael Duch. "So I turned to Silk Road."

Today was the eighth day of the Silk Road drug-trafficking trial, in which Ross Ulbricht stands accused of being the mastermind behind the Silk Road, the Web's most successful drug marketplace.

The testimony that Duch gave had been alluded to in opening statements, when a government lawyer explained how Silk Road "made it possible" for the man, who had never sold drugs before, to quickly become a big-time dealer.

Duch is 40 years old, with a receding hairline and dark beard that has a white patch on his chin. He wore his prisoner's uniform on the stand: a plain black V-neck shirt over a long-sleeve white shirt.

Before he turned to drug dealing, Duch was an IT guy. He worked on a freelance basis, a consultant on networking and security, ultimately starting his own company in 2012. He was making around $75,000 annually at that time.

"Yet, you're here in prisoner's clothing today," said prosecutor Serrin Turner.

"Yes," said Duch. He'd been arrested outside a post office in Monroe, New York, in October 2013, just after Ross Ulbricht was arrested. He'd gone there to send a couple dozen packages of heroin in the mail to his customers.

Duch spoke in a slow, measured tone, describing his own personal path to the Silk Road. Around 2008, a doctor prescribed opiate painkillers to Duch for sports injuries he'd received. "Being that I took those opiate pain relievers for a substantial period of time, I developed an addiction," he said.

He also developed a tolerance, needing more and more for the same effect. "I eventually found out that heroin was just as effective as the painkillers, and it was way cheaper," he said.

Duch bought the heroin in small glassine bags, sometimes called "stamps" on the street because they feature pictures or names as kind of branding. Before long, Duch was using 30 bags a day. When he stopped using, he'd get sick within a few hours. "Sweating, vomiting, diarrhea—extreme flu-like symptoms," he explained.

Despite those difficulties, Duch got clean in 2009. But in 2012, he relapsed—again starting with prescription pain-killers, again finding them too insufficient and too expensive, and turning to heroin. He was spending $200 to $300 a day on the drug. He burned through his own salary, then his savings. He shoplifted from a Target, but got caught. And then he went to Silk Road.

By the time of his arrest, he was making $60,000 to $70,000 each month selling heroin. Most of the money was re-invested into his sales business, or went to his own growing habit.

Fast shipping

In the throes of his renewed addiction, Duch was spending more than ever on heroin—up to $3500 in a single week. He was still employed, but making less at IT work.

Turner: Had you ever dealt drugs before? Duch: No, I had not. Turner: Would you have considered selling it on the street? Duch: Never. Turner: Why did you decide to sell on Silk Road? Duch: I saw the relative ease that came with it. There was a personal level of safety, as well as anonymity." Turner: What do you mean by safety? Duch: Safety from being pursued by law enforcement. Turner: Did you have any misgivings about selling illegal drugs? Duch: Yes, I did. It was something that bothered me, on a daily basis. I had an addiction I needed to feed. It was something I didn't like doing.

Duch ponied up $500 as a deposit to become a seller, which he got back after getting good reviews from his first buyers. He never met or communicated with Dread Pirate Roberts, the boss of the site.

He maintained three types of listings: individual bags of heroin, packs of 10 bags and a "brick" of heroin equivalent to 50 bags. He bought the drugs on the street, in New Jersey, at quantities of up to 40 bricks at a time. The price came out to about $3 a bag, which he was able to double—at least—on Silk Road.

"East Coast Style Heroin Stamps x10 (3 FREE!!!!)" read his 10-bag listing, which cost $96.94 at the time of the screenshot shown in court. The prices were listed in US dollars, even though payment always came in bitcoins.

Duch didn't know much about correct packaging, but he learned it from reading Silk Road forums, he said. Photos of some of his packages, presumably purchased by law enforcement, were shown in court.

"This is a silver moisture barrier bag," he explained as a series of photos were shown. "Inside that was a hair towel, I would use that or CD holders...inside that, another moisture barrier bag custom cut to fit the order." Inside that were the individual bags of heroin, stamped 'Hot Shots' in a bright red font.

Duch's listing, under the seller name "deezletime," had extensive information about shipping. If no shipments would go out on a particular day, he let his clients know.

"Was fast shipping something you marketed?" Turner asked.

"Yes, I had same-day shipping," Duch said. If he got paid by 3:00pm, customers' package would be in the mail the same day. "Users of heroin, they want to know that their product is in the mail when they order it. They're going to go through withdrawal symptoms. These buyers wanted to know, when their money was in escrow, it was in the mail.

Even with his explicit shipping guarantees, Duch got many messages from buyers worried they wouldn't get their order in time.

"Is there any way to overnight this?" asked a customer, in one of several messages Duch got that were shown to the jury today.

"I just wanted to double-check because I am EXTREMELY dope sick," wrote a new buyer on the site, going by the handle "moderngoose."

"Hey bud, just need some confirmation," wrote another. If the dope didn't arrive soon, "I'm going to be sick for the beautiful weekend we have coming up in New York."

"All the time, every day," Duch said. "I got those messages every day."

Detailed records

Early on in his testimony, Duch explained that he has a deal to get a letter from the government sent to his judge, explaining that he was a cooperative witness, in exchange for his truthful testimony. Duch hasn't yet been sentenced, and could face up to 40 years in prison for the drug charges he's facing, with a mandatory minimum of five years. He hopes to lessen that punishment with the help of the government's letter, which could potentially get him a sentence even under the mandatory minimum.

Duch's listing explained that if the Silk Road went down, as it had on a few occasions, customers should look up his "deezletime" account on Atlantis or Black Market Reloaded, two other Darknet drug-dealing sites. Even though Duch maintained seller accounts on those markets, more than 99 percent of his business came from Silk Road. (Atlantis and Black Market Reloaded are both down now.)

"You were an IT guy," said Turner. "Why did you need to deal on any of these websites? Why not launch your own?"

"There was an infrastructure already in place at Silk Road, and it was successful," said Duch. "There were buyers, sellers, and a fair amount of publicity that the site had received."

Even though it was explicitly against the rules to keep customer addresses, Duch kept them all. Every deal he'd done was recorded on a massive spreadsheet that the government acquired when it arrested him. Once he agreed to cooperate with the authorities, he was able to detail his business down to the last deal. He'd taken 2,414 orders, for a total of 31,827 bags—more than three kilos of heroin.

“You were high all the time”

The government ended its questioning of Duch after about one hour. Defense lawyer Joshua Dratel had only a few minutes to begin his cross-examination, and he went in aggressively.

"You have a prior felony," Dratel pointed out. "It could double the mandatory minimum...It's something the government is holding over your head."

"It's never been mentioned," Duch said.

At the peak of his use, he was doing 600 to 700 bags of heroin a week, Dratel pointed out. "So you were basically high all the time?"

"I used it on a daily basis," Duch said.

"You were high all the time," Dratel said.

Duch: "I used four to five times a day," Duch said. Dratel: "So you were high 24 hours a day." Duch: I think there's a difference between being high on heroin [and doing it to avoid feeling sick.] Dratel: You went from pain killers to heroin because you wanted to get high right? Not because you were in pain. Duch: It was a cheaper alternative. Dratel: Are you saying getting high had no appeal to you? Duch: I'm not going to say it had no appeal. Dratel: You want to get high. It was a huge factor, right? Duch: It was a factor.

Dratel's cross-examination of Duch will continue tomorrow. Prosecutors have said they have three witnesses remaining, and their case is likely to end early next week. The defense has said they'll present eight witnesses. Questioned by the judge at the end of court today, they declined to say whether Ulbricht will testify.

Today was the eighth day of the Silk Road trial. For complete trial coverage, see our series page.