BIRMINGHAM, Ala. — For over six years, Roger Shuler has hounded figures of the state legal and political establishment on his blog, Legal Schnauzer, a hothouse of furious but often fuzzily sourced allegations of deep corruption and wide-ranging conspiracy. Some of these allegations he has tested in court, having sued his neighbor, his neighbor’s lawyer, his former employer, the Police Department, the Sheriff’s Department, the Alabama State Bar and two county circuit judges, among others. Mostly, he has lost.

But even those who longed for his muzzling, and there are many, did not see it coming like this: with Mr. Shuler sitting in jail indefinitely, and now on the list of imprisoned journalists worldwide kept by the Committee to Protect Journalists. There, in the company of jailed reporters in China, Iran and Egypt, is Mr. Shuler, the only person on the list in the Western Hemisphere.

A former sports reporter and a former employee in a university’s publications department, Mr. Shuler, 57, was arrested in late October on a contempt charge in connection with a defamation lawsuit filed by the son of a former governor. The circumstances surrounding that arrest, including a judge’s order that many legal experts described as unconstitutional and behavior by Mr. Shuler that some of the same experts described as self-defeating posturing, have made for an exceptionally messy test of constitutional law.

“You’ve got a situation where sometimes there’s no good guys,” said Ken White, a former federal prosecutor in Los Angeles who writes about and practices First Amendment law.