On a cold morning in January, FBI agents converged on a modern brick office building in Koreatown in a mission conjured up at the highest levels of Washington: to rid the world of adult films by an obscure niche producer named Ira Isaacs.
From his 12th-floor suite above Wilshire Boulevard, Isaacs, a stout, fast-talking 56-year-old Bronx native with a short ponytail and a lopsided "soul patch" of black hair under his lip, sent out some stomach-churning porn.
Agents seized Isaacs' files and scanned his computer hard drives, and in July he was indicted on federal obscenity charges.
He pleaded not guilty to six felony counts of transporting obscene material and two counts of not properly documenting the ages of performers, although there is no allegation that they were underage.
Isaacs was barely known in the $4-billion adult entertainment industry in Los Angeles; his films, featuring bestiality and defecation, catered to a tiny audience.
Yet his was the first obscenity case brought in Southern California by a Justice Department task force formed in 2005 after influential Christian conservative groups demanded a crackdown on smut.
The task force's focus on bit players such as Isaacs demonstrates the difficulty of prosecuting pornography in an era when it is more pervasive than ever, with hard-core films offered by major hotel chains and cable companies, and X-rated content of every type exploding on the Internet.
Specifically, it raises a question of whether increasing public acceptance has shifted the legal standard of obscenity -- once aimed at the works of such authors as James Joyce, Henry Miller and William S. Burroughs -- so that only the most extreme margins of porn can be stopped.
The conservative groups who pushed for the initiative say no, and complain that it is virtually pointless to go after fringe figures whose material does not have the societal impact of big commercial productions.
Many federal prosecutors, meanwhile, feel obscenity cases are not worth the time and resources they take away from their main missions, such as stemming terrorism and organized crime.
By focusing on the most distasteful, extreme material, prosecutors are "picking off the low-hanging fruit," said Loyola Law School professor and former federal prosecutor Laurie Levenson. "What does this accomplish? That is the question. These cases take a lot of prosecutorial resources."
