Three former NatWest bankers extradited to the US to face fraud charges arising from the Enron collapse are to appear before a court in Houston, Texas.
Giles Darby, David Bermingham and Gary Mulgrew, who all deny wrongdoing, will learn if they are eligible for bail.
They arrived in Houston around 2000 BST on Thursday and spent the night at a federal detention centre.
The extradition of the "NatWest Three" has sparked a political row in the UK over US powers to extradite.
When the men arrived they were finger-printed and identified by officials before being taken to the detention centre where they were given green boiler suits to wear.
The detention centre is a modern, concrete building with slit windows, described as "grim" by lawyers who had been inside it.
Critics have attacked the extradition system between the UK and the US as one-sided because the Americans have yet to ratify a treaty between the two countries.
Critics also say it is unfair that the US authorities need only to outline the alleged offence, and provide "evidence or information that would justify the issue of a warrant for arrest in the UK" whereas British police must provide the American courts with evidence of "probable cause" if it wishes to extradite someone.
Prime Minister Tony Blair has told the House of Commons that US prosecutors would not oppose bail if appropriate conditions were met.
But the men's UK solicitor, Mark Spragg, said it looked unlikely the men would get "meaningful bail".
"The US prosecutors are currently suggesting they may get bail but only to live in the immediate Houston area.
"That won't be satisfactory at all because they're going have to put up all their money and property as collateral even to get that sort of bail.
"They won't be able to work in the US so they won't be able to earn money to pay their lawyers so I fail to see how they can get a fair fight on that basis."
If the men are not granted bail they could spend up to two years in jail before their case comes to trial.
If found guilty, they could spend up to 23 years in jail without the chance of parole.
Mr Darby, from Lower South Wraxall in Wiltshire, Mr Bermingham, from Goring in Oxfordshire, and Mr Mulgrew, from Brighton in Sussex, are accused of making over £1m each out of a complex fraud in which their former employer NatWest was an alleged victim.