rom Watergate to Iran-Contra, special prosecutors have tended to conduct investigations that last for years, leading to an endless stream of damaging news stories about documents, subpoenas, and sometimes criminal indictments and even convictions. It would be no surprise, then, if Mueller’s investigation lasted beyond Trump’s presidency. All the while, White House staffers will inevitably be distracted and fearful about being dragged into the maelstrom. Meanwhile, the House and Senate inquiries will be chugging along, with leaky committees providing regular (and often slanted) headlines for eager reporters.

Mueller’s inquiry will have its limits, too. Democrats immediately began calling for an independent commission that would have a broader mandate—to look not only at whether crimes were committed by any of Trump’s associates, but also to understand what exactly happened during the 2016 election and make recommendations for preventing future foreign meddling.

And the investigation could be short-circuited by Rosenstein, who has final say on decisions made by Mueller, including whether individual suspects should be prosecuted. The attorney general would normally have that authority, but Attorney General Jeff Sessions has recused himself from any investigation tied to the 2016 campaign. Under the Justice Department rules for his new job, Mueller is required to prepare a confidential report to Rosenstein about his findings at the end of his investigation; the decision about whether to release the report publicly is left to the department.