Judge says case involving Labour MPs David Chaytor, Elliot Morley and Jim Devine established an important point of law

Three MPs convicted of making false expenses claims do not have to pay back legal costs incurred in their battle to avoid criminal trial by claiming parliamentary privilege.

A judge ruled it would not be "reasonable" to expect David Chaytor, 62, Elliot Morley, 59 and Jim Devine, 58, to pay the ?140,000 defence costs of hearings at the court of appeal and supreme court because the point of law established was "of public importance".

Chaytor, former Labour MP for Bury North, and Morley, a former Labour environment minister, were ordered to repay other legal aid sums granted for their hearings and subsequent convictions at Southwark crown court.

Chaytor, jailed for 18 months after admitting three charges of false accounting, was ordered to repay ?23,036 out of a total of ?80,932, as well as ?23,176 prosecution costs.

Morley, the former MP for Scunthorpe, was jailed for 16 months after admitting two charges of falsely claiming mortgage payments. He was ordered to repay ?33,005 out of ?77,980 plus ?23,176 prosecution costs.

Devine, the former Labour MP for Livingston, was jailed for 16 months after a jury trial on two counts of false accounting. He was not asked to repay any of his ?75,216 legal aid as he has been declared bankrupt.

Eric Illsley, 56, the former Labour MP for Barnsley, was jailed for 12 months. He did not contest the charges against him and was ordered to repay his ?10,909 legal aid bill and ?12,187 in prosecution costs.

Arguing the MPs should repay full defence costs, Louis Weston, representing the legal services commission (LSC), said: "Why should defendants, who could have afforded to fund themselves but chose instead to fund themselves at the hand of the state, be in a better position than someone who has chosen to fund themselves?"

Jim Sturman QC, for Chaytor and Morley, said any costs order should take into account the fact the MPs were "unemployed and probably unemployable", and there was very little they could do "to improve their situation in future by way of income".

While their current assets were "sufficient to meet the order", they would have to raise the money through disposal of some of those assets.

Weston had argued that the public purse should not pay "rich" MPs for the legal appeals over the parliamentary privilege issues because the costs incurred "flow" from the defendant's criminal conduct, and also it was their "choice to pursue" that defence.

But, exempting them from payment, Mr Justice Saunders said that the parliamentary privilege point "was one which had to be decided and had to be argued". Saunders added that if the defendants had not done so, "I would have done so and would have appointed counsel to argue it which would have been at public expense," to ensure a fair trial, he said.

He continued: "While some prominent politicians and members of the public may have found the answer to the question of privilege easy to arrive at, from a legal perspective that was not the case."

It raised "difficult issues of law" and he considered it would not be "reasonable" for the defendants to pay the costs.

"Where in the criminal jurisdiction a case raises a point of law of general public importance in my judgment it may not be reasonable to require the defendants to pay the costs of their part in establishing this important point of law or public importance."