BOSTON — A lawsuit brought by a former altar boy who alleges he was sexually abused as a child in the 1960s by a now-deceased Catholic bishop and other clergy can proceed, the highest court in Massachusetts said in a decision released Thursday.

The man from Chicopee identified in court papers as John Doe alleges in the suit filed in February 2021 that not only was he abused by former Diocese of Springfield Bishop Christopher Weldon as well as two priests, but also that the church engaged in a years-long coverup to protect the bishop’s reputation.

The diocese sought to have the suit dismissed based on charitable immunity and the doctrine of church autonomy, derived from the First Amendment.

The Supreme Judicial Court, which upheld a lower court’s decision, said charitable immunity does not apply because, “The abuse allegedly carried out by Weldon and other church leaders was not, and could not be, related in any way to a charitable mission.”

As for church autonomy concerns, those “can be addressed on appeal after final judgment if a lower court inadvertently rules on a religious issue,” the court said.

The diocese victimized the plaintiff when he was an altar boy and continues to victimize him to this day for the way they are handling the case, said his attorney, Nancy Frankel Pelletier.

“On behalf of my client, we are grateful that the Supreme Judicial Court has made it crystal clear that the diocese cannot hide behind the cloak of immunity any longer,” she said.

The high court did dismiss one of 14 claims in the lawsuit that sought to find the bishop negligent for hiring church personnel who allegedly abused the plaintiff.

“The diocese is grateful that the Massachusetts Supreme Judicial Court dismissed the negligence claim brought against it in the Bishop Weldon abuse civil action but is disappointed that the court declined to adjudicate the other issues in the appeal — indicating that it was premature to do so until after the civil case is tried,” the diocese said in a statement.

Weldon served as bishop from 1950 until 1977 and died in 1982.

A retired Superior Court judge hired by the diocese to look into the case found in June 2020 that claims of abuse regarding Weldon were “unequivocally credible,” and that there was a “reluctance to fervently pursue an evaluation of allegations against (Weldon) due to his prominence and revered legacy in the religious community.”

Pelletier said she will now file a motion for summary judgment in the case, which seeks a jury trial and unspecified damages.

She said the diocese has not offered to settle.