I disagree - the burden proof is quite rightly on the pollster or the person using the poll to justify a point of view or action.
I was not clear enough - allow me to restate the sentence:
That said, I can certainly see how attacking the poll itself would be an excellent touche if it's structure is such that it is meant to provide biased results, but that burden of proof is on you, the assailer, to prove your point by explaining how the poll is not credible.
I agree, Daiwa, we should be critically minded of polls, but it is the role of the individual countering the poll to point out how and in what way it's data is skewed.
There is no 'burden of proof' on the pollster as they are not the ones attempting to discredit themselves. They have only to honestly describe their procedure(s) in justifying the resulting data they have retrieved.
Though it could be argued authors writing persuasive pieces should be bluntly honest in their writing and should never use 'unfair' data, even 'correct' data can be used deceptively.
For example, let's take a page from Col. Gene's talking about his unsourced poll:
That truth of that is reflected in all the polls about the Bush policies and the fact almost 75% of Americans believe we are, as a nation, moving in the wrong direction.
...and rephrase it in a manner White House Press Secretary Scott Mclellan might find more conducive:
The truth of that is reflected in all these polls about the Bush policies and the fact almost one third of Americans believe we are, as a nation, moving in the right direction.
Now, can it be seen how it is the personal responsibility of the reader to pick through the b.s. and critically digest what they are reading or being told? If one is given the results of a poll, should they not research the poll themselves then determine the credibility of that poll in their mind? If one is to criticize the poll to others should they not give reasons as to why the poll is not credible?
No person writing a blog should have to, up front, give a detailed explanation of the procedures of the poll every time they quote a number, but they should provide some source so that critically minded readers can check the validity of the poll by their own judgement and explain that judgement to others.