But Roberts pays attention to media coverage. As Chief Justice, he is keenly aware of his leadership role on the Court, and he also is sensitive to how the Court is perceived by the public.

There were countless news articles in May warning of damage to the Court - and to Roberts’ reputation - if the Court were to strike down the mandate. Leading politicians, including the President himself, had expressed confidence the mandate would be upheld.

Some even suggested that if Roberts struck down the mandate, it would prove he had been deceitful during his confirmation hearings, when he explained a philosophy of judicial restraint.

It was around this time that it also became clear to the conservative justices that Roberts was, as one put it, “wobbly,” the sources said.