I would possibly ask if they are happy about working for the company and maybe a few more questions about the corporate culture.
It is not considered to be inappropriate at all and in some interviews this has been part of the interview process. Here are some helpful hints during your interview staying both positive and on track.
If you could describe your corporate culture in three words, what would you say?
This question accomplishes several goals. First, it's creative. That positions you as a thinker, not just another resume. Second, it challenges the interviewer to boil down the essence of their workplace in only a few words. Finally, your interviewer's response isn't as important as how she responds. Watch her body language. Check her posture. And keep an eye on her facial expressions. Look for consistency between actions and words to get the true description of the culture. Because someone's body never lies to you.
If you were going to give public tours of this company, what stops would the guide make?
This is another creative question to challenge your interviewer. What's more, her answers will represent the "greatest hits" of the company's culture. This delivers invaluable insight into what they perceive as the leading attributes of their company. After all, you wouldn't make it a stop on the tour if it didn't symbolize a core component to the company's culture, right?
If the local paper were going to run a four-page article about your company's culture, what would be impossible not to include?
Creative, challenging and counterintuitive. Also positions you in a positive light, regardless of the answer. And, similar to the tour question, this allows your interviewer to put her company in the best light. The secret is, by suggesting a newspaper article it reveals the parts of the company's culture that she would want the public to know about. Transparency is key.
What's the best part about working in this environment that I won't be able to see from just a walk around the office?
This question digs deep into the true value of working in a particular company environment. You learn the culture behind the culture, as some workplaces are quite different once you've been employed there for a few months. This might be helpful in eliciting a little candor in your interviewer about the reality you'd be working in. Sometimes culture is hard to discern from a brief walkthrough or few weeks of work.
What are the most common complaints employees make about your company culture?
Although you want to keep your interview as positive as possible, throwing a monkey wrench into the interview gears might not be a bad idea. Especially because it's an unexpected question. The cool part is, by discovering the negative aspects about a company before working there, you know what to expect. Like visiting Portland during wet season (September through May) before deciding to move there. At least there's no sugar coating.
May I speak with a few of your veteran employees or new hires?
Some companies will already schedule this experience into the interview process. On the other hand, some companies will not allow you to contact existing employees. Either way, asking such a question — and, if you're lucky, getting an affirmative answer — will provide the best insight into corporate culture, as it comes from a team member himself. If you can make it happen, you'll be glad you asked. Because behavior is the broadcaster of attitude, and attitude is the reflection of culture.
What do you love best about the culture here?
Finally, try getting personal. Find out what brings your interviewer back to work every day. Find out what prevents her from leaving the company and going somewhere else. This example is your best tool as a "final" question to ask toward the end of the interview. Just be sure not to ask it too early. Wait until you've created a connection and built rapport with the interviewer. That way you'll be guaranteed an authentic answer
Remember: Company culture is everything. You can't work where you don't fit.
Ask a few of these questions on your next interview, and you'll be sure to find the organization that's the right environment for you.
Yes, it's fine - they may already do it. When you get into a serious battery of interviews, check the list of people to see if a peer is included. If not, ask the interview coordinator if it's possible to spare someone's time when you come in - say you'd really like a peer's perspective on the work and the company.
I like @Michael Grubey's potential question list. You'll probably want to pick and choose - often a single answer can lead off a great discussion better than any formal list. One thing to be aware of is that whether it's private or not, an employee is unlikely to say "this place is awful... don't come!". Misery loves company, and bad mouthing your employer - no matter how private - is a bad idea. So "are you happy?" may get you a hard to read response, where something more tangential may be more enlightening.
Most productive is to focus on opportunities, important aspects of culture, and the personal qualities that the company most values - that lets the employee speak positively while still painting a picture about aspects of the company you want to be aware of.