Five members of the notorious Johnson clan who netted more than £80 million in raids on stately homes have failed in their challenges against their convictions and sentences.

Gang members Daniel O'Loughlin, Richard "Chad" Johnson, Ricky Steven Johnson, Michael Nicholls and Albi Johnson were all convicted at Reading Crown Court of conspiracy to commit burglary with intent to steal in February last year.

O'Loughlin, 32, and Chad Johnson, 33, got 11 years, Nicholls, 30, received 10 years, Albi Johnson, 24, got nine years and Ricky Johnson, 55, got eight years.

Yesterday, the five men tried unsuccessfully to have their convictions and sentences overturned at London's Court of Appeal.

During a day-long hearing, lawyers argued that "bad character" evidence given by the Crown should not have gone before the jury.

Jurors heard that O'Loughlin, Richard Johnson, Michael Nicholls and Albi Johnson had a string of previous convictions.

Lord Justice Maurice Kay, Mr Justice Stadlen and Mr Justice Holroyde, were told that, even if the trial judge was right in letting the jurors hear about that, he had not protected the gang members from prejudice during his summing-up of the case.

But the appeal judges said the trial judge was right to allow bad character to go before jury, and his summing up had not rendered the convictions "unsafe".

There was no bad character evidence in the case of Ricky Johnson, and his lawyers argued that he had been unfairly prejudiced by association. But Lord Justice Kay said he could have no complaint either.

The judges also rejected arguments that the sentences imposed were "manifestly excessive" and should be cut.

Describing the offences as "near to the top end of the scale", Lord Justice Kay said the court was "unpersuaded" that the sentence challenges should succeed.

Items taken from some of the burglaries were found in the possession of O'Loughlin, who was also linked to the crimes by a number of vehicles used and mobile telephone evidence.

Chad Johnson was found with items of stolen property and linked to vehicles used. Ricky Johnson and Nicholls were also linked to vehicles used in relation to the burglaries, as was Albi Johnson. He also went to Cheltenham General Hospital with serious leg injuries shortly after a burglar jumped out of a first floor window at Stanton Harcourt.

Ricky Johnson is the father of Chad and Albi Johnson, while O'Loughlin and Nicholls are related by marriage.

The Cheltenham-based gang plundered tens of millions of pounds worth of precious art and antiques in 16 burglaries across southern England between April 2005 and April 2006.

It included Britain's biggest ever domestic burglary from Ramsbury Manor House in Wiltshire, which netted them £80 million alone.

Burglaries occurred at stately homes in Gloucestershire, Berkshire, Oxfordshire, Warwickshire, Wiltshire and Worcestershire.

It wasn't alleged that all five men were involved in every burglary, but the Crown said each of the raids involved at least one of the gang, and alleged that those involved had a detailed knowledge of the area and local contacts.

At trial, all five said that they were not involved in any of the burglaries.