If there were a Las Vegas betting line about the upcoming Synod of Bishops on the family in Rome, the prospect of a press for a streamlined annulment process in the Catholic Church would probably be a strong 2-1 favorite.

Assuming that one of the major fault lines in the Oct. 5-19 summit will be whether the church’s ban on divorced and remarried Catholics receiving communion ought to be relaxed, making the annulment process more user-friendly looms as a potential compromise measure that could give most camps at least some of what they want.

For that reason, annulment reform is where the smart money about the meeting’s outcome might well go.

Unlike divorce, which is premised on the idea that a real marriage is being dissolved, an annulment is a declaration from a church court that no marriage existed in the first place because it didn’t meet one or more of the tests in the church law for validity.

In some cases, those tests involve procedure. For instance, church law requires that a couple’s vows be received by a Catholic priest, so if a Protestant minister officiated at the wedding, the union could be found null on the grounds of “lack of form.”

In other instances, the problem is substantive. One or both spouses, for example, could be found to have lacked the psychological capacity to truly understand their vows at the time they were married.

Officially the Catholic Church regards marriage as a lifetime commitment, so the annulment procedure is deliberately slow and cautious, although a bit less so in the United States. With just 6 percent of the world’s Catholic population, America accounts for somewhere between 55 and 70 percent of the approximately 60,000 annulments granted each year worldwide.

Defenders of the American system say that’s because bishops in the United States have invested heavily in building up tribunals and training canon lawyers to make the process work.

Critics, on the other hand, call the church in the United States an “annulment factory.” Sheila Rausch Kennedy, who fought a long and ultimately successful battle against former US Congressman Joe Kennedy’s attempt to annul their marriage, has called the United States “the Nevada of the annulment world.”

Even in the United States, however, many people who have been through the process complain that it’s time-consuming, expensive, and invasive in terms of the personal detail that’s required.

For sure, the number of annulments granted by church courts in America is small relative to the number of divorced Catholics. A 2007 study found that in the United States, nearly 10 percent of Catholics are divorced and remarried 10 years after their first marriage, a figure that rises to 18 percent after 20 years.

That’s millions of divorced Catholics out there, few of whom ever bother requesting an annulment.

In terms of the politics of the looming synod, there are three basic camps on what to do about divorced and remarried Catholics, and running the numbers explains why annulment reform is a good bet.

  • One constituency believes it’s time to revise the communion ban, on the grounds of compassion and outreach.
  • Another thinks that’s a no-go because it would undercut a doctrine that comes from Christ himself and because it would weaken the church’s defense of traditional marriage. But this camp wants to do something more for the divorced and remarried.
  • The third group believes the dimensions of the problem have been overstated, because faithful Catholics understand and accept the present discipline.

Though membership in these camps is not evenly distributed, the basic math is that it may be tough to get a consensus about relaxing the rules on communion. There’s a strong majority, however, in favor of some other solution, with annulment reform as the obvious place to start.

One sign of momentum is that even in Italy, where only a third of annulment requests are actually granted, there’s growing pressure to expand the grounds for recognizing a marriage as null.

In February, a conference of church lawyers in the Italian region of Liguria proposed adding “mamma-ism” to the list, meaning a situation in which spouses are so completely under the thumb of one of their parents – usually, according to these jurists, the mom – that they don’t have free will.

Whatever one makes of “mamma-ism” as a legal or psychological concept, it illustrates how eager many Catholic officials are to make annulments more user-friendly.

Another possibility for reform comes from Cardinal Sean P. O’Malley of Boston, who in an interview with The Boston Globe in February floated the idea that annulments could be sped up by eliminating the possibility of appeal to Rome, a provision that often means a case can drag on for years if one of the parties wants to contest the result.

A third possibility is that the Vatican could encourage more affluent churches in North America and Europe to help build tribunals in other parts of the world, for instance by providing scholarships for church lawyers to study in their universities, or releasing some of their canonists for short-term assignments to help develop a local system.

Speeding up the annulment process is not a slam-dunk, however, because there’s also a strong constituency that believes the system is already too loosey-goosey.

Both Popes John Paul II and Benedict XVI voiced notes of caution, calling for judges in church courts not to hand out annulments automatically, and at the grassroots groups such as “Save Our Sacrament” are dedicated to helping spouses who don’t believe their marriage was invalid to fight back.

Moreover, many church lawyers in Rome and in other parts of the Catholic world have long regarded the relatively fast-track American system as an aberration, and would likely resist any move perceived as “Americanizing” global practice.

No immediate decision will be made in October, since this synod is actually preparing for a larger one — the world Synod of Bishops, which will include more bishops, at the Vatican Oct. 4-25, 2015.

We’ll get a sense soon of how it looks to the bishops and other participants gathering in Rome next month … and, ultimately, how it looks to Pope Francis, who will be the one making the final call.