An application for the extradition of a Co Wicklow man to face trial in the US over alleged links to a drugs distribution website is under way at the High Court.

Gary Davis, 27, from Johnstown Court in Kilpedder is wanted on charges of conspiracy to distribute narcotics, conspiracy to commit computer hacking and conspiracy to commit money laundering.

Mr Davis is opposing the application and will argue that he should not be surrendered to the US.

US authorities claim the website known as the Silk Road was an underground site that hosted a "sprawling black market bazaar" on the internet where items including drugs, firearms and counterfeit money were bought and sold.

It was shut down by the FBI in 2013. 

Mr Davis is accused of being an administrator for the website. He was arrested in 2014 and is now on bail.

Counsel for the State Remy Farrell SC said Mr Davis was alleged by the US Government to be the site administrator for the Silk Road website.

This was said to offer services ranging from illegal drug supply to software designed to hack into bank ATMs or Facebook accounts.

He said a diplomatic note from the US alleged the website operated as an Internet market similar to Amazon or Ebay, where sellers and buyers can conduct transactions, but it was designed to facilitate illegal commerce by ensuring absolute anonymity on both sides.

Mr Farrell said the website provided for the sale of drugs within the US, in either individual or bulk quantities, including heroin, cocaine and LSD.

He said that Mr Davis was alleged to have been part of a conspiracy to distribute narcotics in violation of federal laws, on dates between June and October 2013 when he was working for the website.

The maximum penalty for this is life imprisonment, which crosses the threshold of a minimum one year potential sentence required for extradition, Mr Farrell said.

It was claimed Mr Davis used the pseudonym 'Libertas', and that he had dealt with queries from users.

Mr Farrell said it was claimed Mr Davis had also "reorganised the different categories in which the different controlled substances were sold, which discloses an explicit knowledge of the nature of items of sale".

He said the second count facing Mr Davis was of conspiracy to commit computer hacking.

Counsel said Silk Road was a platform for the purchase of malicious software designed for computer hacking, such as password stealers, remote access tools, banking trojans and key stroke loggers.

He said one vendor was offering to hack into Facebook or Twitter, to read, write, upload, delete or view all personal information.

Methods for hacking an ATM machine were also on sale, as was a black market contact list for anonymous bank accounts or counterfeit bills, he said.

The court heard Mr Davis was accused of a third count of conspiring to commit money laundering.

Mr Farrell said the US Government claimed to have evidence that the site was used to launder the proceeds of drug trafficking and computer hacking.

He said bitcoin had been used for all transactions.

"Bitcoin is a decentralised and anonymous form of electronic currency," he explained. "It is clearly fundable and negotiated for via conventional currencies using a fluctuating exchange rate."

Mr Farrell described the allegations as a "textbook example of money laundering".

He said evidence for the three counts alleged had been gathered in the US by US authorities, and included undercover purchases made, along with evidence taken from Internet servers used and from devices allegedly used by Mr Davis' co-conspirators.

Counsel for Mr Davis, John O'Kelly told the court they would be opposing the extradition application on a number of grounds.

He said the request was deficient in a number of ways including the lack of clarity in the charges.

He said aside from being allegedly an administrator of a website, there was a total absence of specific allegation against his client.

Mr O'Kelly said there were no factual allegations on the manner in which he was alleged to have committed any offence except to describe him as an administrator of the website.

He said the charges themselves were extremely vague and duplicitous and the court had not been provided with the detail necessary to decide if the offences alleged against him were ones for which extradition could be granted.

He said there was  a lack of clarity and particularity in the charges.

Another ground of objection was the failure of the State to give adequate consideration to prosecuting him in Ireland.

Mr O'Kelly said if the alleged offence were committed in Ireland then the DPP was obliged to consider prosecuting him for the offences here.

The third ground for objection was the conditions under which Mr Davis was likely to be detained while awaiting trial in the US.

He said there was a real risk of being exposed to a range of unconstitutional measures which would amount to a denial of justice.

Mr O'Kelly said his incarceration while awaiting trial could lead to inhumane and degrading treatment which would be particularly harsh and difficult as he suffers from Aspergers and depression.

In the event of him being convicted, he would most likely be held in a medium security prison which would be totally inappropriate for someone with his mental health state, Mr O'Kelly said, describing his client as a "vulnerable person".

He added that incarceration even while waiting for his trial could cause a serious deterioration in his health.

The hearing is expected to last a number of days before Mr Justice Paul McDermott.