The Clinton entourage is known for their faulty memories under oath, but Bryan Pagliano is setting a new standard. The former Clinton aide chose Tuesday to ignore a congressional subpoena.

The House Oversight Committee held a hearing to dig into some of the issues surrounding Hillary Clinton’s private email server. Mr. Pagliano, who worked as an IT specialist for Mrs. Clinton’s 2008 campaign and set up the private server in her New York residence in 2009, was issued a subpoena compelling attendance.

Mr....