It's theatre.

They are basically trying to put you in an uncomfortable situation to see how you react. You reaction shouldn't be ‘what’s wrong with this guy? what did i do to him?' Instead, try to imagine they are a frustrated client that you, the associate on the case, were tasked to connect with and put at ease. Do your best and regardless of how they act stay professional. 

Sometimes before an interviewing round starts, the interviews agree each to take on a certain persona. On a simplistic level, one can be ‘the good guy’ while the other can be the ‘bad guy’, but realistically they are both as good or as bad. They are just trying to test you and see how you'd react in a similar yet real situation. These situations will come, believe me ;)

Such occurrences are not common, but are not rare either.

In a real life cases - clients can be irrational and are many times biased against you. An interviewer can very well decide to put you under pressure to see how you take it.

You must understand that most interviewers would do this only on purpose. Think of it like a game. When an interviewer starts going rogue - just tell yourself that it's a role play where your role is to play the steely eyed consultant, while the interviewer tries to play a tough client.

If you set this psychology in your mind - such rounds can become easier to tackle.

Please message me with more details of what happened so I could suggest you some specific tricks.

PS: answers to your additional questions in the comment:

1. "They ask a question…": Many people become highly unstructured when responding to this question. You must stay organized and stick to your framework when answering. Thats the first battle. If you have run out of all possible ideas, then you can confidently say that that is all. Be bold and confident in putting the pen down.
2. “Prove it situation…”: Sure it may not be related. After all, no one is born with their future role in their mind. The key is to highlight qualities and learnings from that incident that may be relevant. The whole episode may not be as relevant
3. “Strange business situations…”: You will often encounter clients that behave like that. If you are confident of your answer, then you should stand by it. However, doesn't mean that you should tell the interviewer that they are wrong. The objective is to showcase mediating skills and an approach that can help you resolve the conflict. Try to convince the interviewer and at the same try to see their point of view.

(editiert)

Hi,

This really shouldn't happen. Am sorry if you experienced this!

Interviewers go through training before they are cleared to conduct interviewers. But human behaviour is complicated and any number of things could trigger a bad day. 

However, in the unfortunate scenario if this happens, you have all the right to stop the interview should you feel the interviewer's behaviour is unprofessional or prejudiced. Report to HR and request to reschedule the interview. You must remain polite & professional to make your case clean & strong.

But if you are unable to guage this, don’t make things too personal or take things too seriously. The interviewer could just be having a bad to trying to create a pressure situation to see how you perform. So, try and be relaxed & professional as much as possible. This is not a matter of life & death and all you can really do is to remain focused and give your best. You can’t control outside situations or dictate the interviewer’s behaviour. Neither is every interview going to be great, nor is every interview going to be bad. But you can try & ensure that you continue to be present and just give your best.  

Hello,

This is a tough situation than isn't very common, but does happen from time to time. In most cases the interviewer's attitude has nothing to do with their perception of your candidacy - they are either stressed/having a bad day, or they are using role-play to see how you would react to an unpleasant environment like that. I know it feels unpleasant, but all you can do in that situation is stay calm and proceed through the case and fit exactly as you prepped. If you feel like the interviewer keeps cutting you off or asking the same question over and over again, you could ask them to clarify what it is they are looking for. But I wouldn't assume that just because you don't get along with a particular interviewer, you don't have a chance.

Hi there,

First of all, I am sorry to hear in case you are talking about a situation that has happened to you!

This is indeed an interesting question which is probably relevant for quite a lot of users, so I am happy to provide my perspective on it:

• Generally speaking, during the interview, there is hardly anything you can do besides trying to please the interviewer depending on the insights you might get on him/ her.
• Interviewers will be trained over and over again to get rid of unconscious biases yet as they are all human, it might still happend that an interviewer does not have his/ her emotions under control. At best, he/ she should seek a replacement for the day, however, from my own experience, the least interviewers do so unfortunately.
• However, if you might get rejected at one point in the recruiting process and you have the strong feeling that, independent of the feedback, it was solely because of an unconscious bias of one interviewer, I would advise you to reach out to HR. You need to be very cautious with this and at best have the very polite and objective conversation exclusively via telephone. Based on the experience of coachees of mine there is the chance to re-do an interview.
• Lastly, contradictory to what other coaches said, based on my own experience, the ones of my coachees and my personal network, there is no consulting company that lets their interviewers “act” in a certain way to challenge the interviewee for the following reasons: 1) Consulting companies have a high interest in you having a positive experience irrespectable of the outcome of the recruiting process, 2) there exist many different ways to challenge a candidate that do not require coming off unprofessional and 3) it simply is unprofessional to “act” and pretend something that is not.

In case you want a more detailed discussion on how to best handle such an admittedly tricky situation, please feel free to contact me directly.

I hope this helps,

Hagen

Hi there,

First, I'm sorry to hear about this experience.

I have a few points to make:

1. First, I don't know if you can tell that this is bais. The interviewer may have had a particularly bad day, or is just that type of person. 
2. Second, if things go wrong, you just need to press forward - this is life
3. Third, get used to it. The odds that you get treated poorly on the job (by the client, Partner, project lead) are seriously high. It's the nature of the job. You should get prepared for this to happen again
4. Fourth, if you get notification that you did not progress to the next round, you should reach out to HR. You need to be very careful here. Make sure your email (or, better, call) is very objective. I have heard of instances where another attempt is allowed…but you really have to prove that the interview was out of the norm

Sorry to hear.  I can't think of a consultancy where the hiring decision isn't made by a group of interviewers and so frankly, I think it also speaks a lot about the company you are interviewing with. Your interviewer is not going to be the only exception. 

What exactly is the bias that you sensed from the interviewer?

Hi!

They might be playing the role of the bad cop.

When you interview with a consulting firm you should always be yourself, smile, and never think the interviewer wants to fail you!

Best,

Anto