But his departure will not end the legal entanglements he and the Boston Archdiocese face. Nor will it relieve the pressures that have brought the archdiocese to the brink of financial ruin.
Cardinal Law is scheduled to be questioned by lawyers representing alleged victims of abuse starting tomorrow and he has been subpoenaed to testify before a grand jury investigating a possible cover-up by church officials. On Saturday morning, he arrived at Rome's Fiumicino airport for the flight home, one day after his resignation was accepted by the Pope.
An airport employee confirmed that Cardinal Law left on a flight, but would not specify his destination. Vatican press officials released no details.
What Cardinal Law will do now remains unclear. He is still a cardinal, which means he could be moved to another church post.
Archdiocese spokeswoman Donna Morrissey said Cardinal Law, 71, plans to "take some time and decide what the future will hold for him".
"All things considered he's doing OK," Ms Morrissey said. "But what we have to remember here is to put the victims and the archdiocese and the community of the faithful first."
Cardinal Law resigned on Friday to a "deeply saddened" Pope John Paul II, becoming the highest-ranking US church leader toppled by the furore over the sex abuse scandal engulfing the Roman Catholic Church.
"It is my fervent prayer that this action may help the Archdiocese of Boston to experience the healing, reconciliation and unity which are so desperately needed," Cardinal Law said. "To all those who have suffered from my shortcomings and mistakes, I both apologise and from them beg forgiveness."