News yesterday that the Vatican is investigating Bishop Robert Finn of Kansas City-St. Joseph, Missouri, first reported by Joshua McElwee of the National Catholic Reporter, is potentially a prelude to the most significant step Pope Francis may ever take with regard to the church’s child sexual abuse scandals.

Francis has already met with victims, pledged himself to zero tolerance, and launched a criminal procedure against a former archbishop and papal diplomat accused of paying underage boys for sexual acts in the Dominican Republic. He’s also created a new papal commission to lead the press for reform.

While those moves were arguably important in demonstrating Francis’ resolve, none really broke new ground. Even the trial of the former papal diplomat, while novel in that it’s taking place in a Vatican court, builds on prosecutions in other venues of prelates accused of committing abuse themselves.

What would be new in the Finn case, if he’s removed or otherwise sanctioned, is that a bishop would be held accountable not for the crime of sexual abuse, but for the cover-up, meaning failure to respond appropriately when someone else under his supervision is accused.

In September 2012, Finn became the first US bishop to be criminally convicted on those grounds when he pled guilty to a misdemeanor count of failure to alert police of charges against one of his priests, Shawn Ratigan. After admitting to taking pornographic images of children, Ratigan eventually was sentenced to 50 years in prison and also laicized, meaning expelled from the priesthood.

The indictment against Finn charged that he learned about images found on Rattigan’s computer in December 2010, sending him away for counseling and ordering him to have no contact with children. Police were not informed until May 2011, after Finn was told that Ratigan was still taking lewd pictures of minors.

Finn was sentenced to two years of probation for that delay in making a report, and has remained the bishop of the diocese.

Though victims and their advocacy groups have several complaints with what they see as a sluggish response from the church to the abuse scandals, none looms larger than accountability. The criticism is that “zero tolerance” remains words on paper until there are consequences for failing to make it stick, and to date there hasn’t been a clear-cut case in which a pope imposed accountability in that sense.

The fact that Finn has remained in power following a criminal conviction has made him a lightning rod for this perceived lack of accountability, meaning that if Francis were to act in his case it would have wide symbolic resonance.

The investigation is being led by Archbishop Terence Prendergast of Ottawa, Canada. Such a Vatican investigation of a bishop, usually conducted under the auspices of the Congregation for Bishops in Rome, is rare but not unprecedented.

It’s already happened twice under Francis, once in 2013 with regard to Bishop Franz-Peter Tebartz-van Elst in Limburg, Germany, the “bling bishop” who spent more than $40 million remodeling his residence, and again this year with Bishop Rogelio Ricardo Livieres Plano from the small diocese of Ciudad del Este in Paraguay, accused of being a divisive force in the bishops’ conference and other offenses.

The Livieres Plano case might have been a turning point on the scandals, since one of the complaints was that he had sheltered an Argentine priest accused of sexual abuse in the United States, but a Vatican official clarified that wasn’t the basis for the move.

Further back in time, Bishop William Morris of the Toowoomba diocese in Australia was removed in 2011 following a Vatican inquest led by Archbishop Charles Chaput, then of Denver and now of Philadelphia. In that case, charges included Morris’ support for women priests.

It remains to be seen if the current review of Finn, known in Vatican argot as an “apostolic visitation,” will lead to his resignation or removal. One thing that does seem clear is that the time it takes to reach resolution has been abbreviated under Francis.

Chaput’s review of Morris took place in 2007, but Morris wasn’t forced to resign until four years later. The inquiry into Tebartz-van Elst took place in September 2013, and by the next month he was assigned to an unspecified period of sabbatical. He resigned in March 2014. Similarly with Livieres Plano, Francis dispatched an investigator in July and the bishop was removed by September.

In that light, we may not have to wait long for a denouement in the Finn case.

Read more from John Allen about bishop accountability in his Sunday column, “All Things Catholic.”