The laws of Massachusetts are not clearly defined pertaining to social gambling situations. It is clear that a player who loses any money or thing of value may reclaim that loss, by law, within three months, but the actual legality of playing home poker games is not referenced in Massachusetts General Law.

[Reference, MGL Chapter 137 Sections 1-7: http://www.mass.gov/legis/laws/mgl/gl-137-toc.htm]