FORTUNE – Getting into an elite law firm or management consulting firm may seem like a game of meritocracy: may the best-credentialed win, and may those with well-placed connections come in second. But what you play and whether you'd be fun to play around with after work may count much more than you think.
Excelling in the right sport could advance you to a second interview, and being likable -- or a look-alike to your interviewer -- may be crucial to landing a position at professional services firms, according to new research from Northwestern University. Such connections could give candidates an advantage over someone more qualified who doesn't share the same cultural interests or background as their interviewer.
Employers value feelings of comfort, validation, or excitement when meeting with job candidates over a prospect’s superior cognitive or technical skills, according to the research paper published in the American Sociological Review's December issue. Some interviewers even bent the rules to advance a candidate with a similar cultural or socio-economic background as their own. They would consciously lower the technical bar for candidates with whom they had a great spark.
"Because of the long hours on the job, I really want to select someone who I would personally get along with and would like," says Lauren A. Rivera, an assistant professor of management at Northwestern University. Often, employers want someone "who will be their friend" or even a lover, she says.
One investment banker in Rivera's study said he emphasized a candidate’s social fit because "you will see way more of your co-workers than your wife, your kinds your friends…. So you can be the smartest guy ever, but I don't care. I need to be comfortable working everyday with you … and then going for a beer after. You need chemistry."
Rivera interviewed 120 professionals at investment banks, law firms, and a management consultancy. All were working professionals, not human resources professionals or recruiters, who were sent out to interview undergraduate or graduate students from Ivy League schools. All the candidates were considered talented because of their affiliation with those top universities.
Often, these professionals were told to hire people who were intelligent, great communicators, and had solid social skills, with no guidelines on how to evaluate those qualities, Rivera says. "So they use themselves as a proxy to judge 'is that person going to be good on the job?'"<!-- more -->
Rivera says she found it surprising that leisure activities mattered so much at firms where workers often travel all week and devote 70-plus hours to their jobs, suggesting that it might reflect the interviewers’ notions that work should be fun, and "you're not just hiring a worker, you're hiring a whole person."
"No one has any time to pursue these extracurricular activities once they get in their career," she says, except at a few firms where running marathons gives you status.
A majority of the hiring managers ranked cultural fit -- the similarity to existing employees’ backgrounds, hobbies, and presentation -- as the most important criterion during a job interview.
One consultant and former athlete discounted the leadership abilities of someone who served as an editor-in-chief or president of a club in favor of those with sports experience. He ranked two athletes he met with highest and declined to interview those with a higher grade point average from more prestigious schools but no sports background.
One interviewer argued against inviting back a candidate for a second interview, saying, “He did well on the case and was very articulate. He’s a very interesting guy with a good story. But I think he’s too intellectual…. You know, he is very into 18th-century literature and avant-garde film…. I don’t think he’d be a good fit.”
Yet some recruiters claim Rivera's research doesn’t fully reflect hiring practices today. At many companies, "cultural fit is a broader term" that includes how people interact and get things done and their leadership style, says Elena Bajic, founder and CEO of online career network IvyExec.com. Bajic says that companies are developing analytic tools to determine whether a candidate will fit with an organization's culture, based on the notion that it’s a solid predictor of a candidate’s longevity and likelihood of success. That may not mean a candidate plays the same sport or have the same hobby as their bosses, Bajic says.
"In 30 years of recruiting, I've never seen anyone get a job specifically because they share an interest in hockey with the potential employer," says Jeff Zinser, president of Philadelphia area-based Right Recruiting.
People are primed to connect more easily with others who share their values and interests, Zinser argues, but they balance that with the need to hire the best person for an opening. Otherwise, they face the consequences of a bad or mediocre hire.
Northwestern’s Rivera agrees that hiring managers she interviewed had a very different definition of cultural fit than a human resources person or executive might have. But, in many cases, these hiring managers are on the recruiting world’s front lines at professional schools, weeding out candidates.
As she was finishing her paper and began work on a book on the same subject, Rivera says she talked to her students at Northwestern's Kellogg School of Management about her findings. "They say, 'That's totally how it is…. The question is not 'can they do this job?’ The real decision is, 'Do I want to have beer with this person?'"