A county court judge has threatened to strike out claims by 20 bank customers who are suing for the refund of overdraft charges.
Bank customers may now find it harder to win their claims
District Judge Ian Besford, in Hull, said the claimants were unlikely to succeed because Lloyds TSB had won a similar case recently in Birmingham.
It is the first time a judge in the UK has quoted this case as a precedent.
However, it leaves the legal position unclear as other judges have usually found in favour of claimants.
Several people suing Lloyds TSB, Barclays and HSBC have contacted the BBC about Judge Besford's decision.
His order states that he plans to strike out their claims on 4 July, as they disclose "no reasonable prospect of success in the light of the recent decision" at Birmingham county court.
In that decision, revealed exclusively by the BBC news website, Kevin Berwick lost a claim for £2,545 against Lloyds TSB.
It was the first time that a judge had examined the legal issues involved.
Normally when claims get to court, judges find in favour of the claimants because the banks fail to turn up to defend themselves, and thus the legal issues go untested.
Marc Gander, a spokesman for bank charges campaign the Consumer Action Group, said:
"Kevin Berwick lost in his case in Birmingham because he didn't supply enough evidence.
"This judge in Hull seems to be striking out the claims before he has even seen the detailed evidence of each claimant."
Judge Cooke in Birmingham took the view that the bank's charges were legitimate fees for a package of services and not penalty charges that might be deemed illegally high.
Although his ruling did not set a formal precedent, other judges are entitled to read it and decide, if they wish, that they agree with his arguments.
"It is a judicial decision," explained Barry Hunter - Kingston-upon-Hull court's manager, said of the latest order.
"It is entirely up to each judge to decide for himself if the Birmingham judgement is an interpretation of the law he agrees with," he said.
But one of the 20 Hull claimants, Mark Freer, queried Judge Besford's decision.
"Why not look at the judges who throw out the cases?" he asked.
"Some judges complain the banks don't turn up, or settle just before."
The inconsistency that is emerging in the way the judicial system is dealing with these cases suggests that the success of a claim may soon depend on which court, or even which individual judge, hears the case.
Part of Judge Besford's order
Another recent claimant in Hull, Nicole Haslam, said: "I have recently obtained £5,000 in charges from HSBC and my husband is in the process of taking action to recover around £3,000."
However her husband has now been told that his case may now be struck out next month.
The claimants in Hull have seven days in which to object.
If their objections are unsuccessful they can then appeal to the designated civil judge for the Humber area, Judge Thorn QC.
Another of the claimants, Dave Jeffrey, said he planned to continue with his claim for £1,294.
"It is a bit strange because the Birmingham case was not a precedent," he said.