Amid widespread dispute over the usefulness of polling in determining who should be allowed to appear in presidential debates, a survey of top pollsters suggests that some leading professionals in the polling industry believe that their product is not an effective tool for that purpose.

The issue of minimum polling requirements being used as a qualifier for debates is currently causing significant controversy in both major political parties’ primaries, as both of them now use ever-changing polling minimums to narrow down the number of candidates throughout the election cycle, and in the general election, in which the Republican and Democrat controlled Commission on Presidential Debates requires independent candidates to meet a nigh-impossible 15 percent minimum threshold of support in national polls.

Politico conducted a survey of the opinions of top pollsters and found that many of them believe that public opinion polls lack the precision to measure the small-scale changes in support that determine the rankings between candidates.

Rutgers University professor and former president of the American Association for Public Opinion Research said, “Polls are being used to do a job that they’re really not intended for — and they’re not as qualified for as they used to be. It’s like asking a scale that can only tell pounds to measure ounces. They’re just not that finely calibrated. … I think polls can do a good job talking about tiers of candidates in name recognition. That’s all that polls can do. But they can’t tell the difference between Bobby Jindal, who’s not in the [Republican primary] debate, and Chris Christie, who is.”

Pew Research Center associate director Jocelyn Kiley cautioned, “These numbers all have a margin of error around them. We try very hard, as do most of our colleagues in the field, to make clear when there are significant differences and when there aren’t.”

In a packed Republican primary, the differences between the amounts of support obtained by, for example, a fourth place candidate and a sixth place candidate often fall within the survey’s margin of error.

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Worse still, some otherwise-eligible candidates are not included in nationwide polls in the first place. Presidential Debate News notes that Democratic presidential candidate and Harvard Law School professor Larry Lessig is on pace to be excluded from CNN’s October 13 Democratic presidential debate due to the fact that he has not obtained at least 1 percent support in a specific set of polls that do not include him as a response. Lessig did garner 1 percent support in a September Public Policy Polling survey that is not included in the Democratic National Committee’s list of qualified polls.

Politico’s Steven Shepard pointed out the fact that Senator Rand Paul’s ability to qualify for CNBC’s upcoming October 28 Republican presidential debate hangs in the balance over a statistically-insignificant “0.25 percent — essentially, a matter of two respondents in all the [qualified] polls put together.”

[RELATED: Petition: A Joint Town Hall with Rand Paul and Bernie Sanders]

Marist College Institute for Public Opinion director Lee Miringoff suspended GOP polling in advance of Fox News’ first Republican presidential debate of the season in protest as he objected to excluding candidates on the basis of early polls. “It’s a problem when it’s shaping who gets to sit at the table,” Miringoff told Politico.

The issue is particularly alienating for independent voters, who are forced through taxation to fund the primaries of the Democratic and Republican parties. The top two parties’ nominees automatically qualify for general election presidential debates. However, independent candidates must obtain 15 percent support in nationwide polls to qualify for participation in presidential debates, fifteen times the level of support required for entry-level qualifications for many Democratic and Republican party presidential primary contests. That minimum 15 percent requirement effectively blocks independents, like Green and Libertarian Party candidates who lack the wealth to promote themselves to celebrity status but who sometimes qualify for nationwide ballot access, from appearing in even one presidential debate, preventing them from having an opportunity to share their platforms with voters.

For context, the Truth in Media Project released a Consider This video earlier this year highlighting the fact that independent voters now outnumber Republicans and Democrats. Watch it in the below-embedded video player.

https://www.youtube.com/watch?v=Uf26DKntwzM