Ross Ulbricht, the founder of the Silk Road illegal drugs website, has lost an appeal against the life sentence without parole he has been serving since 2015.

Ulbricht was sentenced to life in prison for creating and acting as the administrator of the Silk Road, a marketplace which lived on the dark web — an anonymous part of the internet hidden from the likes of Google.

After being caught by the authorities while logged into the administrative side of the site in a library in 2013, Ulbricht was found guilty of drug trafficking and money laundering charges. He was handed 'kingpin status' and a life term without parole.

Ulbricht, 33, had argued that his conviction violated his Fourth Amendment rights, which protects against unreasonable searches and seizures of property, and denied him his right to a fair trial. Ulbricht also argued that his sentence was unreasonable, and creating the website in 2011 made the illegal narcotics industry safer, removing dealing from the streets and applying a feedback system to promote preferred buyers and sellers over those deemed less trustworthy.

But the 2nd US Circuit Court of Appeals in New York upheld the life sentence without parole. As well as referring to the "staggering" $182m (£140m) of drugs sold through the Silk Road between 2011 and 2013, the appeals court sided with a lower court's previous belief that Ulbricht had arranged several attempted murder-for-hires to protect his anonymity as the boss of Silk Road. Although there is no evidence anyone was murdered as a result of his demands, the court felt Ulbricht meant what he asked for.

Circuit Judge Gerald Lynch wrote in documents released on 31 May: "That he was able to distance himself from the actual violence he paid for by using a computer to order the killings is not mitigating. Indeed, the cruelty that he displaced in his casual and confident negotiations for the hits is unnerving. Thus we cannot say that a life sentence was outside the 'range of permissible decisions' under the circumstances."

Lynch also noted: "The fact that Ulbricht operated the site from behind a computer, rather than in person like a more prototypical drug kingpin, does not make his crime less serious or less dangerous."

Ulricht admitted early on in his 2014 trial to creating the Silk Road, and operating as its anonymous administrator, known as Dread Pirate Roberts, but claimed he soon handed the site over to persons unknown as its notoriety grew.

In a letter pleading for leniency, Ulbricht said: "I created Silk Road because...I believed at the time that people should have the right to buy and sell whatever they wanted as long as they weren't hurting anyone else. I've learned from Silk Road that when you give people freedom, you don't know what they'll do with it...Silk Road turned out to be a very naive and costly idea that I deeply regret."

'A life sentence is draconian and unnecessary'

Ulbricht's mother Lyn, who runs the Free Ross campaign, said in a statement: "I'm in shock. I feel like I'm reliving the day Ross was sentenced and now must go tell Ross that the Second Circuit has upheld his convictions and double life sentence.

"I can't fathom how the court can believe that keeping Ross locked up for the rest of his life accomplishes anything but wasting a life and lots of money. Do they really think that if Ross emerges in twenty years, after not having been on the internet all that time, he would be a threat to society in any way?...a life sentence is draconian and unnecessary. We will not stop fighting."