It's an interesting article, although not really anything comprehensive. Would be interesting to see / do a fuller examination.
I just did a search on Twitter for "jury duty" and "jury duty" / guilty. Mostly people complaining about jury duty, or celebrating getting out of it.
Michael C. Bromby, The Temptation to Tweet - Jurors’ Activities Outside the Trial, Jury Research Symposium 2010, Institute for Advanced Studies, Glasgow