I contacted a group leader, and he strongly liked my CV. He encouraged me to join his group as a postdoc fellow, but he mentioned that the position he may offer is unpaid (so, I must cover my living expenses).
He mentioned that I can publish good papers in his group following my previous works. Then, I can get a good paid job. So, it is worth of accepting an unpaid job.
I'm wondering if it is common for postdoc fellows to accept unpaid positions?
What the group leader should have said is that s/he has no money, but you can join the lab if you have your own funding (i.e., a fellowship). For them to dangle papers in exchange for free work is unethical and potentially illegal, depending on where they are.
Edit: What follows is entirely my personal opinion. I am no lawyer so no idea about legality; feel free to let me know if you think my opinion is too harsh/wrong.
Any kind of free labour in a lab is unfair and discriminatory. It locks out those in society who aren't lucky enough to be able to give their time away for free. This includes undergraduate internships. If you're working for someone, then you should be paid for your time. Even if you are receiving training.
That would be illegal (for the supervisor/university) in the US.
Edited by popular request to say that like an unpaid internship the US Department of Labor has some pretty strict rules for when an "employer" is allowed to not pay someone who works for them. At my university, postdocing is work, so I think that role should comply with the same rules. At my university a postdoc wouldn't fit either, so in my experience, unpaid postdocs are extremely uncommon.
In the United States, the Supreme Court has stated criteria for when unpaid training or internships are acceptable (quoted from that site):
The training, even though it includes actual operation of the facilities of the employer, is similar to that which would be given in a vocational school;
The training is for the benefit of the trainee;
The trainees do not displace regular employees, but work under close observation;
The employer that provides the training derives no immediate advantage from the activities of the trainees and on occasion the employer’s operations may actually be impeded;
The trainees are not necessarily entitled to a job at the completion of the training period; and
The employer and the trainee understand that the trainees are not entitled to wages for the time spent in training.
In particular, someone can let you do unpaid work for them only when it is for your benefit, not for theirs. I don't know offhand of precedents involving postdoctoral positions, but these criteria seem to me to rule out most forms of unpaid postdocs in the U.S. (Of course, the legal situation could be completely different in other countries.)
In the Netherlands, postdoctoral researchers are considered employees, plain and simple. Such a PI is unlikely to be able to sneak this under the radar, and even if he did - the position is paid, regardless of whether he would like it to be - he's just not making the payments.
It would not be unheard of (although maybe not in the Netherlands) for you do accept this postdoc then sue the guy or the research institute for back-pay - with a good chance of winning... Of course, I wouldn't recommend this strategy if you have a less, shall we say, adventurous opportunity.
From an ethical/moral perspective, I'd also say that PI is acting reprehensibely. Research is important and hard work; true, it benefits the researcher himself as well - but so does almost any professional position where you build a reputation, whether you're a carpenter, or a plumber, or what-not. What's more, the lab or research group benefits from your achievements just as well - you're are fulfilling its goals directly; and your PI benefits also, since his direction of interest in research is being taken further (and that's not to mention partial credit for your work, authorship on papers etc.) ... honestly, if he really "doesn't have the money" - then let all the lab workers, him first, chip in from their own salary so that you all have the same missing fraction of your pay overall.
I disagree with the other answers. In my field, PIs offer postdocs space in their labs even when they have no money for salary. In my field staff is the biggest cost so providing space and consumables and access to equipment is not a problem. During this time, the PI and postdoc might work on grant applications together, but this depends on the situation.
My research is fairly interdisciplinary (probably best described as cognitive neuroscience) and I have seen unpaid post docs in every department I have been affiliated with, including Electrical Engineering, Biomedical Engineering, and Psychology (both in the US and UK). I also have colleagues who have been unpaid postdocs in Neuroscience and Physics departments. My wife is in the humanities and from her colleagues I am aware of unpaid post docs in Art History, English, and History departments (again US and UK).
From the comments, maybe I am overstating what a post doc is. None of the unpaid positions I am aware of had any teaching or supervisory requirements. Nor did they have any binding contracts. What they did is provide the individual with access to an office/lab, library, and internet. In the sciences they often provided access to consumables, IRB/ethics review and approval, and money to run human subjects (when needed). The positions were all "supervised" since someone needed to sign off on them but the postdoc was basically free to do what they wanted.
I do not know of anyone who stayed in the unpaid post for more than 6 months (they usually either got a grant to stay or a paid position someplace else). Most of the people were straight out of their PhD and were in the process of applying for funding. They tended to have strong ties to the city of the post doc.
There seems to be variation in policies regarding unpaid postdocs. Yale explicitly says that unpaid and volunteer researchers are not allowed and from what I can find, they do not allow any unpaid visiting researchers. UPENN does not allow unpaid post docs, but they do allow unpaid visiting scholars which appear to be very similar to postdocs. MIT also does not allow unpaid postdocs, but does allow unpaid visiting positions. Harvard SEAS is the only university in my quick search that allows unpaid "postdocs".
I did an unpaid postdoc in Japan, as my wife was staying there anyway, and I was both young and desperate. I knew of 3 or 4 other people like me, also motivated by a desire to stay in Tokyo at "all cost". I wouldn't say they were common, but they weren't unheard of either.
The rationale was that I would get to publish and given the prestige of the university and the lab I was with, it would be beneficial for my career in the long run, even if I wasn't paid. I signed on as an unpaid postdoc and I made ends meet by teaching English, French and translating technical papers and documents.
My experience was overall negative. Despite being reassured otherwise - I was told I would be treated just like any junior faculty/researcher - people just don't take you seriously if they know you are not paid, and it will be very hard to keep it a secret. The psychological effect became very difficult after a while. I expected most people to admire my perseverance and dedication to my research, by willing to work for free. Instead most people were looking at me as some sort of charity case - "he's working here for free because he can't get a real job". There were several conflicts between my research (what I wanted to be doing), and the part time jobs I was doing. It was very hard to focus on my research, when I was constantly being pulled into some task or event because of my other jobs.
If you are a foreign national in the host country you want to do a postdoc in, you will most likely run into visa issues if you are not paid, and you will run into employment authorization issues for whatever part-time work you want to do to make ends meet. In my case I had to switch from a visiting scholar visa to a dependent visa, then wait a long time to get a part-time work authorization. I've seen foreign researchers in the US (where I live now) face similar problems.
In the US, some states don't allow unpaid post-docs for labor law reasons, and even when it is allowed by local laws, the university itself might have rules against it for security, insurance and liability reasons. The 3 places I am familiar with in the US, Georgia Tech, Emory, and MIT, don't allow unpaid post docs.
Back to my experience in Japan, none of the unpaid post-docs I knew of materialized into real academic positions. They all eventually gave up, and either went back to their hometowns/countries and got low-level teaching positions there or they left academia for the industry - and when you join the industry you find yourself having lost 3 or 4 years compared to other people with your age and skill set.
Conclusion: Don't go for an unpaid post-doc, it's very taxing and it's not worth it at all. There's a world beyond academia.
I have never heard of an unpaid postdoc position, unless you're talking about having some external funding so that no money is going out of your supervisor's pockets.
But maybe you need to provide more information. I think that depending on your country and your area of expertise, it may not be as uncommon as people here think.
I advise strongly against such positions, for multiple reasons.
I am a Principal Investigator at a Swiss University.
In my view, postdocs are experienced scientists who should know how to write a passable project description and application for funding. Therefore I expect all my postdocs to help contributing to the expenses of the lab, e.g. by acquiring competitive fellowships (e.g. HFSP, EMBO, DFG, Marie-Curie).
You may, however, try all of the above - and still fail, for reasons that are out of your control. In that case, I will give you a "safety net" by paying your salary through my core funding. But if you feel that the financial health of my lab is none of your business, and you are not even prepared to try and get some funds, then please do not apply to my lab.
I don't know other countries, and I only know the situations in the U.S.
If you are a postdoc, then you are considered an employee, and the university has to pay you; otherwise, this is a serious violation of labor law, and I bet no regular universities would do this. If you are a visiting scholar to an American university to conduct research, then the university may not have to pay you, but you have to show you have enough funding to support your living expenses in the U.S. These funding could be from your home country, from a research institution, or even just from yourself.
In contrast to the answers here, it's very common and many people here do this everyday. There's a term for it:
Visiting scientist or visiting scholar
(https://en.wikipedia.org/wiki/Visiting_scholar)
Labs that don't have money can offer a visiting position to a post doc. Many people take the job, do it full-time for free.
Everyone who works as a visiting scientist is a free labour. By definition, the number of free post docs in the world is at least the total number of visiting scholar title holders.
Visiting scholar == free work == free post doc
It's legal in all countries. All academic institution like that. Thus, all other answers in this post are simply wrong.
Anyone with a visiting non-paid title is a free post-doc. Simple and plain. Please don't deny it.
Re: Most of the time, salary is contined by the home department, often through sabbatical.
Let's say university is paying you for your job. You get a new job at Mcdonald, but work for free as a "visitor". Are you going to say "I am not making burgers for free because my salary is contined by my home department."?
