Fifty years ago news of Roe v. Wade was leaked to the press. News, not a draft or the written opinion. A clerk talked to a reporter without realizing that the story would appear hours before the decision was announced. The clerk’s apology was accepted; he wasn’t fired or forced to resign.
Fifty years ago Supreme Court documents were typed. Justice Blackmun kept drafts locked in his desk in his office. He was careful not to share his opinion even with Mrs. Blackmun, whom he knew would be pleased with it. The world is different today; court documents are most likely kept on computers, possibly cell phones, and could be emailed.
Investigation seems focused on finding a culprit. The most likely culprit is the Court’s computer system (for which Chief Justice Roberts is responsible) or the Justices themselves, whose devices may have been hacked. We may never learn what happened, but hacking seems a likely explanation.