[5] Following Bash's clerkships, he was an associate attorney at Gibson, Dunn & Crutcher, where his practice focused on complex litigation in federal district and appellate courts.

“Per the A.G.’s policy, we should NOT be categorically declining immigration prosecutions of adults in family units because of the age of a child,” he wrote his staff after a phone call with Rosenstein.

[17] On May 27, 2020, a Justice Department spokeswoman said that Attorney General William Barr had assigned Bash to review practices of the Trump–Russia investigation related to the 2016 "unmasking" of Trump's advisor Gen. Michael Flynn in a phone call with Russian Ambassador Sergey Kislyak.

[20][21][22] Fox News reported that his successor, Gregg N. Sofer, would continue overseeing any ongoing investigations that Bash had led.

Bash wrote he had found no evidence that any unmasking requests were made for any political or otherwise improper reasons during the 2016 election period or the ensuing presidential transition.