In the second installment of their series on a federal investigation into Casino magnate and Republican mega-donor Sheldon Adelson, ProPublica and Frontline focus on how difficult his company has made it for investigators to get their hands on information about its Macau operation. The subject matter here is dense, but it could have big consequences: Adelson and Sands are under investigation for possible violations of the Foreign Corrupt Practices Act. If the feds prove their case before November's election, the biggest single donor on the Republican side could turn out to be in violation of federal law, an embarrassing blow to the Romney campaign. (There were reports two days ago that Adelson might join Romney for his visit to Israel next week.) Frontline and ProPublica's reporting paints a picture of a company doing everything it can to slow an investigation down.

The latest news is that after Adelson's company, Las Vegas Sands, fired Steven Jacobs, the president of its Macau operation, it copied his hard drives and moved them to its Las Vegas office, a lawyer representing Jacobs says. That sounds reasonable, on the surface, except for a couple of things: First, the company reportedly used the hard drives to prepare a defense against a lawsuit it knew was coming from Jacobs. Then, when his lawyers filed their suit and asked Sands to hand over its evidence, the company refused, saying the drives were still in Macau and it couldn't move the information out without local authorities' permission. That's shady but here's where it intersects with the federal investigation: "Federal investigators examining Jacobs’ claims that he had been ordered to overlook illegal activity in Macau faced the same roadblock, [Jacobs'] lawyer told a Nevada judge," reporters Matt Isaacs, Lowell Bergman, and Stephen Engelberg wrote. The filing said only that the company had moved the records "in error."

Last week, the same team of reporters delved into documents that showed payments made by Adelson and Sands to Leonel Alves, a Macau legislator whose law firm also represented Sands. As The Wall Street Journal's Kate O'Keefe reported back in June, Alves allegedly offered to expedite Sands' Macau developments, in what's starting to look, to SEC investigators, like a case of bribery. For now, though, Adelson and Sands are merely under investigation, not the subject of any prosecution.