Archbishop Conti said Mr Martin interited an inadequate system
One of Scotland's most senior Roman Catholic clergymen has criticised MPs for "hounding" Michael Martin out of his job as Commons Speaker.
Mr Martin, who has been criticised over the MPs' expenses scandal, will step down from the role on 21 June.
Mario Conti, the Archbishop of Glasgow, accused some members of shifting the spotlight to deflect attention from their own misconduct.
Mr Martin will also quit as Glasgow North East MP, sparking a by-election.
The contest is expected to be staged in September.
Mr Martin - the first Roman Catholic Speaker since the reformation - was criticised for leading efforts to block the publication of MPs' expenses, since revealed by the Daily Telegraph, and was facing a motion of no confidence in him, backed by more than 20 MPs.
In a letter to the Herald newspaper, Archbishop Conti said the "unseemly and undignified" attacks on Mr Martin reminded him of an "assembly of unruly pupils, seeking to humiliate their headmaster for misdemeanours they themselves had perpetrated".
"The parliamentary culture of greed, selfishness and secrecy, which has been exposed by the press, is shameful," he wrote.
The Archbishop said few parliamentarians had emerged from the expenses row with "flying colours", adding: "To compound the sense of public distress, we have now witnessed some MPs shifting the spotlight away from their own misconduct by hounding the Speaker from office.
"And this despite the fact that Mr Martin inherited the woefully inadequate system, and himself proposed changes which would have gone some way the cleaning up the culture, only for his fellow MPs to reject them.