Suppose you have an issue you are really passionate about – taxes, gun control or some other important policy. You want to do more than vent on social media, so you decide to write an email, place a phone call or even draft a letter to your state legislator expressing your views.

As a citizen, I would praise your sense of civic responsibility and willingness to express your opinion. As a scholar, I would encourage your efforts – they’re more consequential than many people realize.

I teach communication and public policy at Michigan State University and study how constitutents’ communication with lawmakers affects public policy decisions.

In my previous research, I analyzed – with their permission – the efforts of coalitions working to get citizens to contact their lawmakers in support of major legislation in New Hampshire and Michigan. I conducted a rigorous evaluation of the types of contact constituents made, the messages they conveyed and the behavior of lawmakers both before and after receiving those communications.

The results showed that communications from constituents can have a large impact on how legislators vote. For example, emails from constituents encouraging policymakers to support smoke-free workplace bills in New Hampshire increased state legislators’ support on critical votes by an estimated 20 percentage points – a substantial effect.

But a lot of people don’t bother to contact their elected officials, thinking it’s not worth communicating with them.

In today’s polarized political environment, is it possible to get through to policymakers from the other side?

Discounting opposing views

Some work, including my own mentioned above, suggests that policymakers are responsive to communications from the public. But research has also shown that policymakers engage in what’s called biased reasoning, writing off communications from constituents who do not share their policy views.

For instance, political scientists Daniel Butler and Adam Dynes asked state and local policymakers in two online surveys to evaluate a hypothetical communication from a constituent. Policymakers were randomly assigned to evaluate a letter that either supported or opposed a controversial policy and then rated the hypothetical writer letter on various characteristics.

The authors found that policymakers rated hypothetical constituents who disagreed with them as less knowledgeable about the topic. This discounting of constituents who disagree on policy could explain why policymakers tend to have biased perceptions of public opinion, believing the public’s attitudes to be more in line with their own positions than polling suggests.

Is there a way to prevent lawmakers from writing off constituents’ perspectives?

Do your research

In recent work with political communication scholars Hillary Shulman and Dustin Carnahan, I sought to develop strategies to limit policymakers’ discounting of constituents’ opinions.

We asked a national sample of elected local policymakers – among them city council members – to evaluate a hypothetical email writer randomly assigned to express support or opposition to raising the minimum wage. The survey was fielded by Civic Pulse, which specializes in samples of elected officials.

This study was similar to the Butler and Dynes study described above. But we added two randomly assigned conditions – what we called a “read” condition in which the writer expressed having “read a lot about” the topic, without any specific detail, or a “cite” condition in which the writer summarized and cited a study supporting their position.

We anticipated, based on research on biased reasoning, that providing clear evidence that the constituent is knowledgeable about the issue would prevent biased discounting of constituent opinion.

Policymakers in our study were asked to evaluate to what extent they thought that the constituent understood the issue, was representative of the community, and was sincere and held their position strongly, and whether they thought the communication was a form letter rather than a constituent-intitiated communication – and therefore presumably more likely to be written off.

How to not be written off

The results confirmed previous findings that policymakers indeed discount the opinions of constituents with whom they disagree. When policymakers read an email expressing an opinion that differed from their own on raising the minimum wage, the email writer was rated lower across all five dimensions.

However, if the email writer provided evidence that they knew about the issue – citing research supporting their position – policymakers were more likely to perceive that the email writer understood the issue. The effects of citing evidence are stronger than simply stating that one has read about the issue.

My own work suggests that a constituent expressing an opinion to an elected official can influence the official’s vote on the issue. But just writing to an official is no guarantee that the constituent will persuade the official or have the issue resolved in the way they prefer.

Our study is important in identifying a way constituents can avoid being written off.

We also found that there are no downsides to providing evidence supporting one’s position.

You might expect that when provided with unambiguous evidence that a disagreeing constituent understands the issue, policymakers might direct their efforts to discounting other constituent characteristics, rating the constituent as less sincere or less representative of the community.

We did not find any evidence that this happened. When faced with evidence that their constituent knows the issue well, policymakers are less likely to discount their opinions.

How to be heard

The practical results are clear: When communicating with a policymaker, especially one with whom you disagree, you want to stop them from discounting your opinion. One way to do this is by citing quality evidence to support your position.

While this advice seems straightforward, it did not appear in guides we surveyed created by citizen groups like the Sierra Club, ACLU or Christian Coalition.

When contacting a policymaker about an issue, be aware that they may discount your opinion if they disagree.

But note also that carefully crafted communications can convey your position without being written off – and could improve how accurately the policymaker understands public attitudes about public policies.

Daniel E Bergan does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.