Aboard the papal plane • Pope Francis apologized for insisting that victims of pedophile priests show “proof” to be believed, saying he realized it was a “slap in the face” to victims that he never intended.

But he doubled down on defending a Chilean bishop accused by victims of covering up for the country’s most notorious pedophile priest, and he repeated that anyone who makes such accusations without providing evidence is guilty of slander.

Francis issued the partial mea culpa in an airborne news conference late Sunday as he returned home from Chile and Peru, where the clergy abuse scandal and his own comments plunged the Chilean church into renewed crisis and revived questions about whether Francis “gets it” about abuse.

Francis insisted that to date no one had provided him with evidence that Bishop Juan Barros was complicit in keeping quiet about the perversions of the Rev. Fernando Karadima, the charismatic Chilean priest who was sanctioned by the Vatican in 2011 for molesting and fondling minors in his Santiago parish.

Flying home from the most contested trip of his papacy, Francis said Barros would remain bishop of Osorno, Chile, as long as there’s no evidence implicating him in the cover-up.

“I can’t condemn him because I don’t have evidence,” Francis said. “But I’m also convinced that he’s innocent.”

Karadima was removed from ministry and sentenced by the Vatican in 2011 to a lifetime of penance and prayer based on the testimony of his victims, who said they were all molested by him in the swank parish he headed in the El Bosque area of Santiago. A Chilean judge also found the victims to be credible, saying that while she had to drop criminal charges against Karadima because too much time had passed, proof of his crimes wasn’t lacking.

Three of the victims testified before Chilean prosecutors and others have also said publicly for years that Barros, one of Karadima’s proteges, witnessed the abuse and did nothing to stop it.

Barros denies the accusations.

“The best thing is for those who believe this to bring the evidence forward,” Francis said. “In this moment I don’t think it’s this way, because I don’t have it, but I have an open heart to receive them.”

Juan Carlos Cruz, the most vocal of the accusers against Karadima and Barros who testified in court about the cover-up, responded with a statement to The Associated Press: “If he wanted evidence, why didn’t he reach out to us when we were willing to reaffirm the testimony that not only us, but so many witnesses, have been providing for more than 15 years?”

Francis, though, repeated again that anyone who makes an accusation without providing evidence is guilty of slander.

“Someone who accuses insistently without evidence, this is calumny,” he said. “If I say ‘you stole something, you stole something,’ I’m slandering you because I don’t have evidence.”

He acknowledged that he misspoke when he said he needed to see “proof” to believe the accusations, saying it was a legal term that he didn’t intend. He corrected himself and used the term “evidence” instead, which he said could include testimony.

“Here I have to apologize because the word ‘proof’ hurt them. It hurt a lot of abused people,” he said. “I know how much they suffer. And to hear that the pope told them to their face that they need to bring a letter with proof? It’s a slap in the face.”

The Barros scandal dominated Francis’ Jan. 15-21 trip to Chile and Peru, and led to a remarkable church-state public rebuke of the pope.

Cardinal Sean O’Malley, Francis’ top adviser on abuse, issued a public criticism saying Francis’ words were a “source of great pain for survivors” and that such expressions had the effect of making them feel abandoned and left to “discredited exile.” The Chilean government spokeswoman, Paula Narvaez, said there was an “ethical imperative to respect victims of sexual abuse, believe them and support them.”

Francis insisted that he did respect victims and apologized for his “unhappy” choice of words when he was asked by a Chilean reporter Jan. 18 about his 2015 decision to appoint Barros to Osorno over the objections of Chilean bishops.

Francis replied: “The day they bring me proof against Bishop Barros, I’ll speak. There is not one shred of proof against him. It’s all calumny. Is that clear?”

The comments sparked an outcry among Chileans and roiled abuse survivors and their advocates.

The spokesman for a group of Osorno Catholics opposed to Barros, Juan Carlos Claret, said the pope still didn’t get it.

“It’s incredible that the pope doesn’t understand that the problem wasn’t the word ‘proof’ or ‘evidence,’ which is the same thing, but that he accused victims of slander — victims who were found to be right by both Vatican and Chilean justice,” he told the AP.

He noted Cruz had formally testified in 2010 that Barros was present during the abuse.

At the news conference, Francis also explained a letter reported last week by the AP that showed the Vatican was prepared to ask Barros and two other Karadima-trained bishops to resign and take a year sabbatical in 2014 to try to contain the fallout from the scandal surrounding the priest. Francis admitted that he put a stop to the plan, saying that if he accepted the resignations without evidence or “moral certainty” that Barros had done anything wrong, “I would be committing a crime of bad judgment.”

Francis said Barros actually did offer to resign — twice — but that he rejected it.

“I said, ‘No, this isn’t how we roll,’” adding that sending Barros and the other bishops on sabbatical would have been seen as an admission of guilt.

The 2015 appointment outraged Chileans and badly divided the Osorno diocese, where hundreds of lay Catholics and many priests have refused to accept Barros.

Marie Collins, who resigned in frustration from Francis’ sex abuse advisory commission last year, in part over the Barros affair, said she couldn’t bring herself to comment.

“Why comment? It’s a pointless waste of effort,” tweeted Collins, who has become a leading critic of Francis’ abuse record, especially his decision to allow the commission to lapse last month.

Francis said Sunday a new membership roster had been put to him earlier this month and was being reviewed. He denied that the lapse of the committee showed it wasn’t a priority for him.

Francis was also asked about the sex scandal in neighboring Peru regarding the lay movement Sodalitium Christianae Vitae. He revealed that its founder, Luis Figari, is appealing his Vatican sentence on charges of physical, sexual and psychological abuse, and economic mismanagement. The Vatican high court is expected to hand down its sentence in two months, he said.

“What I know is that the thing is unfavorable to the founder,” Francis said.