Open meeting Law guide contains the following information:

What constitutes a deliberation? The Open Meeting Law defines deliberation as “an oral or written communication through any medium, including electronic mail, between or among a quorum of a public body on any public business within its jurisdiction.” Distribution of a meeting agenda, scheduling or procedural information, or reports or documents that may be discussed at a meeting is often helpful to public body members when preparing for upcoming meetings. These types of communications generally will not constitute deliberation, provided that, when these materials are distributed, no member of the public body expresses an opinion on matters within the body’s jurisdiction. Additionally, certain communications that may otherwise be considered deliberation are specifically exempt by statute from the definition of deliberation (for example, discussion of the recess and continuance of a Town Meeting pursuant to G.L. c. 39, § 10A(a) is not deliberation). To be a deliberation, the communication must involve a quorum of the public body. A quorum is usually a simple majority of the members of a public body. Thus, a communication among less than a quorum of the members of a public body will not be a deliberation, unless there are multiple communications among the members of the public body that together constitute communication among a quorum of members. Courts have held that the Open Meeting Law applies when members of a public body communicate in a serial manner in order to evade the application of the law. Note that the expression of an opinion on matters within the body’s jurisdiction to a quorum of a public body is a deliberation, even if no other public body member responds. For example, if a member of a public body sends an email to a quorum of a public body expressing her opinion on a matter that could come before that body, this communication violates the law even if none of the recipients responds.