Opposition deputies have condemned as a "shambles" and fundamentally flawed, legislation for a proposed constitutional amendment on judicial behaviour.

Fine Gael's Justice spokesman, Mr Alan Shatter, called for a postponement of the referendum and Mr Brendan Howlin, Labour's justice spokesman, said that if the referendum was passed "judges will be made more immune from public sanction and accountability".

The Minister for Justice, Mr O'Donoghue, who introduced the 22nd Amendment to the Constitution Bill, said, however, that impeachment procedures would apply to all judges. The constitutional amendment would allow for the establishment of a body to investigate possible misbehaviour by or incapacity of judges.

It would also allow for the removal of a judge by a two-thirds majority of the House instead of the current simple majority. Mr Shatter said the Bill was substantially flawed and fundamentally defective.

"Instead of facilitating the impeachment of members of the judiciary alleged to have seriously misbehaved, it will erect constitutional barriers to impeachment which will render the impeachment procedure practically redundant."

Mr O'Donoghue, who opened the debate, said that impeachment procedures would be similar to those applying to the President. The Sheedy affair had highlighted the need for new provisions on judicial accountability and for better and more detailed provision for removing a judge from office.

The philosophy behind the Bill, the Minister said, was to "provide for fair and workable measures to deal with judicial misbehaviour which serve to enhance public confidence in the administration of justice and it must maintain and support the independence of judges in carrying out their duties".

He said the impeachment procedure "will apply to all judges, not just to judges of the Supreme and High Courts as at present". He believed the two-thirds majority requirement for impeachment was the correct way forward.

"It effectively removes the possibility that such a decision could be taken solely with the support of Government parties and against the wishes of the Opposition."

Mr Shatter said the legislation did not state how many judges would be on the body to investigate judicial misbehaviour, or who would appoint the non-judges to it. The legislation also excluded investigation of behaviour by a judge prior to their appointment, he said.

Mr Howlin said it was "incredible that after all the palpable public anger created by the Sheedy affair, the Government is actually proposing a measure which will make judges more immune to public scrutiny and sanction than ever and even harder to remove from office".