A SENATE candidate backed by Katter's Australian Party has attacked Opposition Leader Tony Abbott in an open letter to leading Australian Catholics, including Cardinal George Pell.
The former national general secretary of the KAP, Bernard Gaynor, wrote to Cardinal Pell and numerous other Australian Bishops on Monday.
Mr Gaynor's letter said it was incumbent on the church to correct politicians when they expressed support for "immoral practices" such as abortion and IVF.
The letter comes only days after Mr Abbott's chief of staff, and Opposition Education spokesman, Christopher Pyne, voiced their gratitude for Mr Abbott's support of IVF.
"In 2004, Pope Benedict XVI, in his role as Prefect, Congregation for the Doctrine of the Faith, published a letter that confirmed the Catholic Church viewed abortion as a grave sin," Mr Gaynor's letter reads.
"He further stated that politicians who consistently campaigned or voted for laws permitting abortion were to be denied Holy Communion.
"In the same year the Federal Opposition Leader, Tony Abbott, in his former capacity as Federal Health Minister, stated his support for legalised abortion.
"By his own admission, Mr Abbott has reaffirmed this position in recent days and engaged in a publicity campaign designed solely to increase public awareness and support of his views."
Mr Gaynor also wrote that Mr Abbott, a Catholic who once considered a future as a priest, had also publicly questioned the church's teaching on IVF, "a practice that frequently involves abortion".
His letter called upon the church to publicly "correct" such political announcements and engage in the public debate over abortion and IVF.
"It is my unhappy experience that, too often, politicians who do vote in accordance with their Catholic conscience are left crucified by the silence of the bishops when they most need public support," the letter reads.
"The failure by church hierarchy to charitably correct or condemn those politicians who support gravely immoral practices means that there is no backing for the few Catholics in politics who are true to their faith.
"It paralyses Catholic political action and dooms the largest religious grouping in this country to irrelevance."
Responses have been sought from Mr Abbott, who is on leave, and the Australian Catholic Bishops Conference.
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