Any good trial lawyer these days is keenly aware that jurors are revealing valuable tidbits about their lives, their interests, and social and political leanings on such services as Facebook and Twitter. But while social media profiles can present a trove of data points for jury selection—one that legal tech companies are eager to mine—researching jurors online while keeping on the right side of the judge and local ethics rules is hardly a straightforward exercise.

“It's really an issue that I see developments on a weekly basis,” said John Browning, a trial attorney at Passman Jones in Dallas and author of “Legal Ethics and Social Media: A Practitioner's Handbook,” set to be published next month. At the end of the day, Browning said, most opinions out there would steer attorneys toward doing more research about their panel over less. Even so, there are nuances depending on what state you're in, and who the judge is.

Here's an overview of how the landscape is shaping up in some key jurisdictions.