Why supposedly good Christian politicians lie

Tony Abbott, the conservative politician on the verge of becoming Australia's next Prime Minister has confessed that people should not believe something just because he said it. The only truths of his that are to be believed are those promises that he has actually written down.
And today we learn that the Australian Tony is not the only Tony who feels no guilt about telling porky pies. The long serving British Labour Prime Minister Tony Blair, like Mr Abbott a man who calls himself a devout and practising Roman Catholic, has a similar attitude towards the truth.
The London Daily Telegraph today ran a story based on the soon to be published Blair memoirs in which Mr Blair admits to “bending and distorting” the truth as prime minister, but says a degree of manipulation and distortion are necessary to govern, and voters accept that. 

“Politicians are obliged from time to time to conceal the full truth, to bend it and even distort it, where the interests of the bigger strategic goal demand it be done. Without operating with some subtlety at this level, the job would be well-nigh impossible.” 

Discussing his approach to the truth, he suggests that, at a deeper level, voters retained trust in him because he was trying to do his best for them. He says the public discriminate between politicians they do not trust at a superficial level — “ie pretty much all of them” — and those they do not trust at a more profound level. This is the level at which the public believes that the political leader is trying to do his or her best for them. “This is the level of trust that really matters.”