Deputy Attorney General Rod Rosenstein should take a page from the playbook of the man whose firing he recommended: former FBI Director James Comey. Comey once stood in Rosenstein’s shoes: He served as deputy attorney general from 2003 to 2005. And Comey’s handling of the investigation into the CIA leak scandal that rocked the George W. Bush administration holds valuable lessons for the current inquiry into the Trump campaign’s ties to Russia.

There are strong similarities between the challenges facing Rosenstein and the ones that Comey previously encountered. Today, the possibility of political interference hangs over the investigation by Robert Mueller, a former FBI director selected by Rosenstein to serve as special counsel. Similar doubts swirled around Patrick Fitzgerald, a US attorney from Illinois whom Comey picked to investigate the CIA leak in 2003.

Much to his credit, Comey recognized that regulations laid out by the prior attorney general, Janet Reno, failed to give the special counsel sufficient independence from higher-ranking officials at the Justice Department. So Comey implemented a more robust set of safeguards to shield his special prosecutor.

Rosenstein has thus far failed to follow Comey’s lead. That’s unfortunate, because it leaves Mueller’s investigation vulnerable to interference by political appointees. A few simple changes would raise the confidence of the American people that Mueller is free to follow the evidence where it leads.

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