A friend gave me written permission to use a picture he took of the Brooklyn Bridge and the buildings behind the bridge on the cover of my novel.
Intellectual Property Law Attorney
Personal photographs of public buildings are legal. You should have no problem with this use. Just be sure to keep a copy of the original photo by your friend and the written permission. You should have the "written permission" reviewed by a copyright attorney to be sure it actually gives you permission.
So far, this is free to you. Until you pay a fee, I am not your lawyer and you are not my client, so you take any free advice at your sole risk. I am licensed in IL, MO, TX and am a Reg. Pat. Atty. so advice in any other jurisdiction is general advice and should be confirmed with an attorney licensed in that jurisdiction.
Patent Infringement Attorney
Mr. Burdick is, of course, right. There is a specific exception to copyright law that authorizes pictures of public buildings or other works of architecture.
That said, make sure you hold on to that written permission. If your novel is successful, it's amazing how fuzzy people's memories get.
Pictures of buildings and bridges can be used without a license from the owner of the buildings of bridges. However, you should make sure that your friend gives you a clear license to publish the photograph in your book. If there is any ambiguity in the written document that he gave you, it could come back to haunt you. It is worth spending a few bucks on a local lawyer to draft a document that would withstand a challenge in court.