You said the image was created for the band but designed by the member who left – absent an express agreement in writing signed by the owner of the right to assign the copyright to the band, he created the work and retains the copyright from the instant he created it. Perhaps you can attribute the copyrighted image to him if he just wants acknowledgement, but come to a new agreement which assigns you or the band the full rights to the copyright (make copies, derivative works, etc).
You may be able to argue he was an employee of the band, which automatically will give the band the copyright, but this will probably not be successful since the criteria examined in making this determination involves his level of independence, if he owned his own instruments, employee benefits, tax forms, etc.
You also potentially have a trademark issue since the image is probably used to identify the band and lead the consumer, or in your case listener/concert attendee, to the band rather than the group member who left. You should contact an intellectual property attorney who can examine the issues to make sure you are not infringing and perhaps draw up some forms for you to clarify which rights belong to which person or group.
DISCLAIMER: This answer is provided for general informational purposes only, is not intended as legal advice, and does not create an attorney-client relationship. Do not rely on this information – it is a starting point for your issue and you should contact a licensed attorney in your jurisdiction.
If in 2012 the band was in the business of making money, rather than creating music simply as a hobby, then when the former member created the logo he likely did it as an employee "work for hire" for the band partnership and so the band, not the former member, is the author of the logo and therefore owns the copyright in the logo.
If in 2012 the band was not yet trying to make money through its music then the former band member is the author and copyright owner of the logo. However, the band very, very likely has a license from the former member to use that logo.
There are many facts to consider when doing this analysis so you need to discuss them all with your own Maine-licensed intellectual property attorney. Good luck.
The above response is general information ONLY and is not legal advice, does not form an attorney-client relationship, and should NOT be relied upon to take or refrain from taking any action. I am not your attorney. You should seek the advice of competent counsel before taking any action related to your inquiry.
I also agree that the argument trying to capture the member as "employee" would likely not be fruitful. There are many cases on the books that speak to this scenario as it relates to partnerships in business and I'm not so sure the body of law would support that, but I would not discount it entirely either.
I think it is more likely that absent a written agreement, the band ended up with an implied license to use the image for its intended purpose but does not have full exclusive rights, which will remain with the creator. This means, that the band can use it in all the ways that normally attend the use of such an image, but they could not, for example, license it to Bono to use on the cover of a new U2 album.
I would caution that yours is a fact intensive scenario and you should not walk away with anything conclusive here in my or anyone's answer really. I suggest that you consult with a lawyer in private and discuss your best course of action moving forward BEFORE you commit to anything in more detail. You can start by calling around to several for a free phone consultation, get some insights then pick the best fit to work with.
DISCLAIMER: this is not intended to be specific legal advice and should not be relied upon as such. No attorney-client relationship is formed with the law firm of Natoli-Lapin, LLC on the basis of this posting.
I think this will end up the property of the band, either by written contract or by implied exclusive license especially if you have proof of authenticity through written correspondence. Whether or not you have such documents, see an IP lawyer at once as using self-help.
I am not your lawyer and you are not my client. Free advice here is without recourse and any reliance thereupon is at your sole risk. This is done without compensation as a free public service. I am licensed in IL, MO, TX and I am a Reg. Pat. Atty. so advice in any other jurisdiction is strictly general advice and should be confirmed with an attorney licensed in that jurisdiction.
You may be able to argue that the creation of the logo was a "work for hire," especially if there is written correspondence that could support the argument. You should speak with an Intellectual Property attorney as soon as possible to negotiate the best possible outcome and ensure that your interest in the logo is protected.