What is Interview Bias and How to Avoid It | Thomas.co

When it comes to hiring the right person, there can be a lot of stress involved in the recruitment process. From sifting through CVs to getting through assessments and reports to track down the ideal candidate. This is compounded by the fact that in the past you might have missed out on the perfect candidate because of something called interview bias. 

We all carry some biases in our subconscious, and interview bias is no different. It can make hiring the right candidate more difficult because interview bias can interfere with objectivity and cloud the judgment of the person being interviewed.

In this guide we are going to take a closer look at interview bias, understanding what it is, the different types of interview bias and how to reduce it when it comes to making hiring decisions. 

What is interview bias?

Interviewer bias is where the expectations or opinions of the interviewer interferes with the judgment of the interviewee. This can either affect the outcome positively or negatively and that these preconceptions can both consciously and unconsciously influence judgment. 

For example, an interviewer may decide that the candidate wasn’t a good fit for the organization because their handshake wasn’t strong enough at the start of the interview or that not enough eye contact was made when answering questions. These are extreme but very common types of negative outcomes in interview bias.

Another form of bias may be that the interviewer feels some sort of affinity towards the interviewee because they like the same football team or share a similar point of view. It’s important to note that some interviewees will answer questions in a manner that is to please the interviewer, clouding that bias further.

Understanding interviewer bias

Interview bias can exhibit in different ways, not least when the interviewer uses language in the questions that exhibit biases or talk about subjects that would be geared towards more personal choices rather than the role itself. For example, the interviewer may talk about what has recently happened in the news - unless you’re interviewing for a news organization, this is loaded with bias as the answer given may result in a variety of different responses.

Of course, interviewer bias can also be due to body language, facial expression etc. These are preconceived notions that have arisen through years of development in the interviewer and whilst many would consider themselves to have little bias, that is ever rarely the case. After all, we are all human, we will develop these ideas over time and we are all subject to it.

The biggest point to note is that interview bias refers to how responses from participants are affected by aspects of the interviewer. From a handshake to the opinions on a particular area of concern, how the interviewer sees those things can make or break the chances of the person being hired - all because the interviewer sees it differently.

How can bias affect a job interview

Interview bias can be against or in favor of a particular candidate over another, and this is where bias can play a significant role in both the interview and the outcoming selection. You must take the measures previously discussed in order to limit bias and remove it from the decision making process. 

What are the types of bias that can affect interviews? Here are some of the most common forms of bias. 


These are generalized opinions formed over time about how people from a given gender, religion or race, think, act, feel, or respond. Example: Presuming that a woman would prefer a desk job over working in engineering is a form of stereotyping bias.

Inconsistent questioning

This is where different questions are asked to different candidates. Example: You may ask a caucasian male candidate to describe what their university experience was like compared to a candidate who is a person of color, where you only ask about work experience.

Negative emphasis

Based on a small amount of negative information, you reject the candidate. Interviewers will weigh negative information twice as much as favorable information. Negative emphasis generally happens on subjective factors such as dress or nonverbal communication which can taint the interviewer’s judgment.

Halo effect

The halo effect is where the interviewer allows one strong point - they personally view it as - to overshadow all the other information presented in the interview. When it works in favor of the candidate, it is known as the halo effect; and when it works in the opposite direction (the interviewer judges potential candidates unfavorably in all areas on the basis of one trait) it is called the horn effect. 

Cultural noise

Cultural noise is about the failure to recognize a candidate’s responses which are socially acceptable rather than factual. For example, the candidate may give responses that are "politically correct" but not very revealing. Example: An employer may comment, "I note that you are applying for a role that has more working hours. How do you feel about that?" The applicant might say that this is fine even though this is not the case.

Types of interview bias

There is not just one type of interview bias, there are plenty and whilst we have covered just a few in the previous sections, it is a good idea to understand just what those types of biases are.

We are going to take a closer look at the different types of interview bias and uncover more in each one.

Stereotype bias

This is a generalized belief about a group of people where the interviewer has a clouded judgment of the candidate based on their social category and not the skills or competencies of the interviewee. It could be that the position requires longer working hours than normal and if there are childcare commitments, a female candidate may be excluded before the interview stage. Other examples of stereotype bias include:

  • Elderly people
  • Disabled people
  • Rich people
  • Gender for the role  (i.e. a man can’t be a receptionist)
  • Poor people

Confirmation bias

Confirmation bias is something we are all guilty of. In the case of recruitment it is when the interviewee is asked questions to confirm or elicit responses that support the preconceived notions about a particular candidate. This ultimately means that the interviewer is only concerned about confirming an idea that they have of the candidate either from a preconception that comes from a CV or application or from the moment that the interviewer meets the candidate and another form of bias may have crept into the interview stage.

Social desirability bias

Social desirability bias or cultural noise bias as it can otherwise be called is when the interviewee changes their answers so that they are more desirable from a cultural perspective rather than expressing their own true thoughts.

Recency bias

Recency bias can occur when the interviewer bases their assessment on recent events and not over a wider period of time. Therefore memories of the most recent interview candidates are stronger. It is sometimes called, contrast effect bias - wherein interviewers compare candidates with the preceding interviewee.

Gender and racial bias

Gender and racial bias are pretty self explanatory. In short, this is when the interviewer will either hold a general view about a certain gender or race or that the role is not suitable for either because of preconceived ideas and notions. It is critical that no interviewer should be influenced by prejudice from both a moral standpoint and a legal one as well. 


Similarity bias

Similarity bias is when interviewers and candidates may discuss hobbies they share or display similar traits in an interview. Hiring decisions based on these similarities rather than a candidate's qualifications may be the result of similarity bias.

Nonverbal bias

Both interviewers and interviewees communicate in a non-verbal manner through body language and eye contact as well through verbal communication. When an interviewer focuses more on the nonverbal aspect rather than the skills of the interviewee this is known as nonverbal bias.

Halo bias

This refers to when one single characteristic overshadows all the other ones for the interviewee. For example this could be where the candidate went to school or in some cases it could be how good looking they are. This will give the interviewee an idea that is positive about all the skillsets of the candidate rather than just one area.

Horn bias

This is in effect the opposite to the halo bias. For example this could be where the candidate may spell something incorrectly on their CV giving the interviewee an idea that is negative about all the skillsets of the candidate rather than just one area.

What is an example of interview bias

There are plenty of examples where we can dive deeper into interview bias. Here is one such example that explains affinity bias. 

Affinity bias is one of the most common types of interview bias. This is where there is an affinity between the interviewer and the candidate, therefore the candidate is viewed in a better light than they should be. Traditionally this could be from something on the C.V. such as the university they went to was the same, or they had the same manager but many years apart. 

However, affinity bias can take place in a moment usually within the interview itself. Let’s say a candidate gets interviewed on a Monday and the interviewer begins with, “how was your weekend?” The response is something like, “Good thank you. I went for a bike ride and did some trails.” The hiring manager is equally a keen cyclist and so they get along. Whether intentional or not, the hiring manager has a favorable view of the candidate, despite the fact that no work-related evidence has been presented yet.

Things like red flags are quickly dismissed from the rest of the interview, and the positive characteristics of the candidate are emphasized even further. 

With something like affinity bias, it is better to use blind C.V’s which limit the amount of personal information one can gather and equally, not to ask personal questions, in, before or after the interview. 

Another good example of interview bias is the Horns effect. 

As previously mentioned, the horns effect is the opposite to the Halo effect. So how does it manifest in an interview scenario? The horns effect means that the candidate has appeared as a “bad” candidate once (maybe briefly) on one item of the interview, and now the interviewer has made up their mind. Anything else, even as accurate as the answer could be will be dismissed or downplayed. 

Finally, another type of bias that is common is attribution bias. Similar to confirmation bias but with a twist, it is another form of cognitive bias but in this scenario, the interviewer will make up reasons for facts and things that happen to the candidate, instead of looking at the facts objectively. They try to craft explanations, or more accurately, to invent explanations.

An example would be the following; the candidate shows up late to an interview and the interviewer decides that they came late because the candidate does not care about the role. The truth however is that the interviewer has no way to certainly assert if the candidate cares or not because they cannot read minds. However, attribution bias will dictate that such behavior does not imply a specific case. 

The interviewer is dangerous in this scenario because they are painting a picture of the candidate based on their beliefs (attribution) and then frames the rest of the interview so that the candidate lives up to such a faulty image (confirmation). 

How to reduce bias in interviews

There are many types of bias that we have discussed, however, it is equally important to understand that removing bias from the interview process helps interviewers to correctly identify the best candidates and be objective.

How can interviewers remove bias from the interview process? Here are some suggestions:

Use an interview guide

This is a document that is put together to help provide a structure for the interviewing process. It helps keep both the interviewer and the organization interviewing in a consistent and compliant manner which should help all candidates  get the same treatment at interview.

Furthermore, this will help interviewers know what to ask and in what order, so as to help provide the same candidate experience for all applicants. Whilst the questions may change based on the industry or requirements for the job, an interview guide can be used to help candidates for a role be treated equally. 

Use standardized questions and scoring criteria

Using standardized questions and a scoring criteria removes many different kinds of bias from the interview process. You can develop a scoring system but then this needs to be standardized across each interview. By doing so, you bring clarity to the decision making process based solely on the information you have from the interview over other potential influencing decisions.

Provide interviewer training

Interviewers must have training on equality and diversity, including how to avoid their own unconscious biases. Not only will this help to minimize the impact of hidden intolerances and prejudices but it will also provide a fairer system for all the candidates being interviewed. 

Training should include things such as:

  • How to avoid asking irrelevant questions that can lead to a bias being made on the character of the person
  • Recognizing how assumptions can be made about applicants
  • Keeping an impartial and open mind and not focusing on things such as looks or body language to affect the evaluation of the candidate

Use anonymized skills based testing

Where possible, you can keep many aspects of the candidate selection anonymous. For example in a skills assessment, you can remove the potential for bias and aid recruitment in decision making by removing things such as name, date of birth and even ethnicity from the records. Keeping this information anonymous allows you to thoroughly assess the skills of the candidate without coloring any judgments.

Use multiple, diverse interviewers

We are of course all naturally biased. What this means is that we need to remove bias at different stages of an interview process, and in some cases use more than one method to help do this. One way to do this is to use multiple interviewers so that the potential for bias affecting the interview process is reduced.

Someone will have less bias in one area than another and vice versa. By opening up the pool of interviewers, you are allowing for more skills to shine through. 


Take notes throughout interviews

Real-time note taking helps minimize the chance of bias. Why? Because notes after the meeting can be tinged with opinions or ideas about the candidate which has no place in the decision making process. Keeping accurate records throughout the interview will help to identify the skills and competencies of the candidate in a clear and concise manner, removing bias along the way.

Minimize unrelated discussion

Whilst there is always room for a bit of small talk to help the candidate feel at ease and at home with the process, making that small talk the topic of conversation can contribute towards bias in the interview. 

Being able to keep the small talk, small is essential. This is where sticking to a script and using a marking method can help with the development of the interview process and limit the level of potential bias.

Use an assessment matrix

You can use an assessment matrix to help identify a candidate based on a number of different criteria, and all without any form of bias creeping in. From job description, person specification and the agreed weight given to each criterion, an interviewer will ensure that all applicants are assessed objectively, and solely on their ability to do the job satisfactorily. 

This will help to ensure that every hiring decision is based on reason and evidence, rather than opinion and potential discriminatory bias.

Recruit broadly

Where you get your candidates from can easily influence the kind of bias that some may have compared to others. For example if you’re only getting candidates from a job board, it may be worthwhile opening up the application process from a job fair or going to higher education establishments and recruiting from there.

This will open up the variety of candidates from different areas to help your interviewers get the most broad range of candidates from different areas which in turn will provide a less biased based evaluation of the interviewee.

When are interviews not the best option?

Sometimes, interviews are not always the best option and it’s easy to forget that they are not the only way of gathering information - depending on the role you are hiring for. As an example, large-scale phone interviews can be time-consuming and expensive whilst mailed questionnaires may provide the best option when it comes to getting information from a large number of people.

Here are some other reasons why interviews are not always the best option; 

  • Phone interviews/screenings for a large candidate base is time consuming and good candidates could be ruled out in early stages due to bias - questionnaires/assessments etc can help
  • Times when only numeric data is required to be collected - instead using forms
  • Some candidates may not perform well in interviews and interviewer bias could affect the ability to see the true potential of a candidate
  • If respondents are unwilling to cooperate, interviews will not be suitable. 
  • If your candidate has something against your organization they will not give you the answers you want and may even mess up your results. Become aware of your candidate’s inclinations quickly so that you can already make the best judgment before interviewing them. 
  • Equally, when candidates struggle to talk or communicate effectively, setting up an interview is a waste of time and resources. You should, then, look for a less direct way of gathering the information you need.

There are also times that when an interview is over, the interviewee wants to go over the copy, change or edit it to make sure that they are addressing any concerns that the interviewer may have. That’s not always a good option - in fact, that shouldn’t really happen but sometimes bias can step in and allow for it to happen. If the subject you're addressing involves technical information, you may have the interviewee check the final result for you, just for accuracy.

Finally there is something which isn’t always considered when it comes to deciding if an interview is the best option or not, that is, do you have a standardized process in place? Research by Schmidt and Hunter has consistently shown that the interview method on average explains an average of 8% variation in employee performance. This means its predictive power is limited when it comes to predicting which employee will perform when put on the job. 

There are a number of reasons why the interview process has such a low level of predictive power, but primarily this is focused on the factor that most interviews are unstructured and unstandardized. This means that candidates who have applied for the same job are sometimes asked questions that have nothing to do with the job hence making it difficult to assess their suitability for the job.
Another reason why interviews show low predictive power is interviewers are poorly trained and rarely come for the interviews prepared. This needs to be something that changes in order to bring a greater consistency to the interview process and in return, bring out the best results from the candidates.

There is however a solution to a lot of the problems that are brought out from interviews, one that can work against the biases mentioned above. That is to conduct interviews and assessments together, so that the process is standardized and better equipped to deal with bias in the first place.


Interview bias refers to how responses from participants are affected by aspects of the interviewer and when done in such a manner, it can lead to interviewers making a bad decision over who should or who shouldn’t be hired. 

We are all biased and the interview stage has many different forms which can affect selection of a great candidate. Being able to limit these biases from the interview process is essential in keeping the organization more responsive to a better crop of candidates for long term success.

The Thomas Recruitment Platform allow candidates to be evaluated fairly, freely and without bias from the information provided interfering in their application. It can also aid your organization in the development of value based questions and analyze results to help make hiring decisions easier. Specifically, the interview guide is dynamically generated for each individual that takes our assessments, and gives you suggested questions to ask in the interviews based on the traits and aptitudes that you define as most important for the role. Using these questions in an interview, you can really get to the heart of each interviewee and understand more about their personality and behavior than you would from a standard interview.

If you would like to know more, please speak to one of our team.