“I personally have a pretty good idea who is responsible, but that’s different from the level of proof that is needed to name somebody,” Alito told the Journal.

“It was a part of an effort to prevent the Dobbs draft … from becoming the decision of the court,” he said.

US Supreme Court preserves access to abortion pill for now

After a sweeping investigation, in January the court said it could not pinpoint the source of the leak.

Alito said it led to the near-attack on Justice Brett Kavanaugh, who was viewed by some as a possible swing voter on the abortion rights issue.

An armed man was arrested outside Kavanaugh’s suburban Washington home in the early morning hours of June 8.

The man told police he had travelled from California to Washington to kill a High Court justice, saying he was upset about the leaked draft and school shootings.

“Those of us who were thought to be in the majority, thought to have approved my draft opinion, were really targets of assassination,” Alito said.

“It was rational for people to believe that they might be able to stop the decision in Dobbs by killing one of us.”

04:38

Protests across US after Supreme Court's decision to overturn abortion rights

Protests across US after Supreme Court's decision to overturn abortion rights

Alito said the threat level rose after the leak to the point that he was blocked by security from speaking in person at a local university last May.

He said that even he now must travel in what he labelled “a tank” surrounded by security.

The leak not only sparked security issues. It also added rancour to relations between the nine justices, said Alito.

The leak “created an atmosphere of suspicion and distrust. We worked through it … But it was damaging,” he said.

The court published its 6-3 decision to overturn the landmark 1972 Roe vs Wade decision guaranteeing abortion rights on June 24.

It drew strong cheers from anti-abortion activists who were energised to carry their fight into the states.

But it left Americans in favour of abortion rights, which polls show are a solid majority, angered and dismayed.

Alito said the whole episode raised the intensity of criticism of the court, which he called “new during my lifetime.”

“We are being hammered daily, and I think quite unfairly in a lot of instances. And nobody, practically nobody, is defending us,” he said.

He faulted the legal community specifically for not defending the High Court.

“If anything, they’ve participated to some degree in these attacks.”

But he said nothing about calls for greater scrutiny over the nine justices, their political leanings and their finances.

On Tuesday, the court’s Chief Justice John Roberts refused to testify in Congress about business dealings by two conservative justices and lavish gifts one received that have raised ethics issues.

US Supreme Court justice accepted lavish trips from billionaire: report

Roberts cited “separation of powers concerns and the importance of preserving judicial independence” in declining the committee’s invitation.

Asked about the allegations against Thomas, a fellow conservative, Alito told the Journal: “I’ll stay away from that.”

After being confirmed for life terms by the US Senate, Supreme Court justices are not required to answer questions from the public.

The last time a justice answered questions in Congress was 2011, and it was over the same issue.

The committee nevertheless plans a hearing on Tuesday on ethics reform for the High Court.