No, you don't not need consent to publish a photo of someone. You need consent to make money off of that photo because you're making money off their likeness. B

No, you don't not need consent to publish a photo of someone. You need consent to make money off of that photo because you're making money off their likeness. But even in that case, it's a civil, not criminal offense. This applies to photography in public. A conference can have their own policy about what is and isn't okay. Although if the convention center is a public building that may complicate things. Even if the conference had an issue with it, it's not illegal.