Regarding the issue of whether an organizer has liability for things that happen in connection with a Meetup group or at a Meetup event, please see this article from our Help Center.
As the above article mentions, some organizers enter into releases directly with their members, separate from the Meetup Terms of Service.
The details of a release and what a release contains depends on the nature and activity of a specific Meetup group, and what kinds of issues the release is meant to address.
Another issue to consider regarding releases is how to get members to sign a release. Some groups have their members sign a paper copy. This can be done either at every Meetup event, or one time upon initially joining the group. You may also have members agree to an online release as part of the group join process. We've seen Organizers add this as part of a required set of profile questions. Also, if a group allows guests at Meetups, consideration should be given as to how a guest will sign a release.
Note: This is general information and not legal advice about any specific situation. Also, the laws regarding liability vary from state to state. You should consult a lawyer for advice about your specific situation.
For more information about liability and releases, here are some online resources to check out:
FindLaw Waiver and Release Forms
Note: The third party sites mentioned above are all independent of Meetup, and Meetup has no involvement with the content on these sites. Also, as indicated on most of these sites, the content on these sites is general information that does not address any specific situation and not for the purpose of providing legal advice. You should consult a lawyer for advice about your specific situation.