VATICAN CITY — Pope Francis has radically reformed the process for annulling marriages, overhauling 300 years of church practice by creating a new fast-track annulment and doing away with an automatic appeal that often slowed the process down.

The move on Tuesday, Sept. 8, which came a week after he said he was letting all rank-and-file priests grant absolution to women who have had abortions, was further evidence of his desire to make the church more responsive to the needs of ordinary faithful.

The new law on annulments goes into effect Dec. 8, the start of Francis’s Holy Year of Mercy, a yearlong jubilee during which the pope hopes to emphasize the merciful side of the church. It will speed up and simplify the annulment process by placing the onus squarely on bishops around the world to determine when a fundamental flaw has made a marriage invalid.

A Catholic needs a church annulment to remarry in the church, and a divorced Catholic who remarries civilly without one is considered an adulterer living in sin and is forbidden from receiving Communion.

The Communion issue is at the center of debate at the upcoming synod of bishops, a three-week meeting that gets underway in October. Progressive bishops favor a process by which these Catholics could eventually have access to the sacrament if they repent; conservatives say there can be no such wiggle room and that church teaching is clear that a marriage is indissoluble.

Catholics have long complained that it can take years to get an annulment, if they can get one at all. Costs can reach into the hundreds or thousands of dollars for legal and tribunal fees, though some dioceses have waived their fees.

“With this fundamental law, Francis has now launched the true start of his reform,” said Monsignor Pio Vito Pinto, the head of the Roman Rota, the church’s marriage court. “He is putting the poor at the center — that is the divorced, remarried who have been held at arms’ length — and asking for bishops to have a true change of heart.”

Reasons for granting annulments vary, including that the couple never intended the marriage to last or that one spouse didn’t want children.

The new law also says that “lack of faith” can also be grounds for an annulment, conforming to the belief of Francis and Pope Benedict XVI before him that a sacramental marriage celebrated without the faith isn’t really a marriage at all.

Francis’ biggest reform involves the new fast-track procedure, which will be handled by the local bishop and can be used when both spouses request an annulment or don’t oppose it.

Previously, most people seeking annulments needed to go before a three-judge panel unless a regional bishop’s conference gave a bishop permission to hear the case himself or to appoint one judge to handle it. The new law makes that an immediate option, meaning annulments should be easier to obtain in dioceses that don’t have enough priests to make up a three-judge panel, which is especially common in poor countries.

The fast-track procedure can also be used when other proof makes a more drawn-out investigation unnecessary, such as medical records indicating that the wife had an abortion, that one spouse hid infertility or some other grave contagious disease from the other, or that violence was used to coerce a spouse into marriage.

The law calls for the process to be completed within 45 days. The longer, regular process should take no more than a year.

Another reform is the removal of the appeal that automatically took place after the first decision was made, even if neither spouse wanted it. An appeal is still possible, but if one of the sides requests it.

Officials said that the new law is not retroactive: The abolition of the automatic appeal, for example, will only apply to annulment cases decided after Dec. 8.

In the document announcing the new law, Francis insisted that marriages remain indissoluble unions and that the new regulations aren’t meant to help dissolve them. Rather, he said, the reform is aimed at speeding up and simplifying the process so that the faithful can find justice.

The overall goal, he said, “is the salvation of souls.”

“It is a democratizing move focused on easing the course of reintegration into the church for women, in particular,” said Candida Moss, professor of Biblical studies at the University of Notre Dame. “His actions are propelled by compassion and pragmatism: He recognizes the dangers of spousal abuse and the reality that many modern marriages are undertaken without full consideration.”

Significantly, the reform places much more importance on the local bishop in handling marriage cases and reducing the need for recourse to the Vatican’s own courts — part of Francis’ overall reform of the Catholic Church itself to decentralize power back to local bishops, as was the case in the early church.

The reform, which was the result of a yearlong study by canonists, is the second major initiative Francis has taken in as many weeks that may have reverberations in the United States, which he will visit later this month. The first was the change in rules about granting absolution for abortions.

Nearly half of the total annulment cases in the world come from the United States, thanks in part to its well-organized tribunal system.

The new reforms might increase the U.S. numbers further, though the Center for Applied Research in the Apostolate at Georgetown University has noted that the overall number of annulment cases in the U.S. and globally has dropped, as the world’s population ages and the number of marriages celebrated in the church declines.

Already, some conservatives have criticized Francis’ abortion initiative as running the risk that some might misinterpret it as a softening on the church’s opposition to abortion. Conservatives have also warned that simplifying the annulment procedure could imply the church is making it easier for couples to essentially get a “Catholic divorce.”

Francis has long called for the church to be less legalistic and more merciful and understanding of the needs of its flock.

In the document, Francis called for fees to be waived, except for the “just” payment of tribunal personnel. But officials told a press conference it will take time for bishops’ conferences to wean themselves off the fees entirely.

Francis has previously quoted his predecessor as Buenos Aires archbishop as saying half of the marriages that are celebrated are essentially invalid because people enter into them not realizing that matrimony is a lifelong commitment.