Trump’s justice department has found a new way for presidents to avoid accountability | Claire Finkelstein

A memo on executive privilege maintains that private advisers to a president can avoid responding to a subpoena by asserting the president’s executive privilege. Critics warn this practice, if accepted by courts, will make it substantially harder to call witnesses regarding possible wrongdoing by presidents. The article cites Don McGahn's refusal to testify using "testimonial immunity" as an example of how the former administration was complicit in obstruction under investigation.