Also, because the laws of the Church and the state typically have different grounds for declaring nullity, the Church will not investigate a marriage in which a decree of nullity is sought until the parties have obtained a civil annulment or divorce. Otherwise, the Church could possibly do damage to a struggling marriage by the process of investigation itself. In fact, if the Church were to do such an investigation, she could be liable (in some places) to civil suits seeking damages for “alienation of affection”. Also, in a case where the Church might clearly declare a marriage null, the state might not recognize the same grounds. In that case, the couple has to obtain a civil divorce before getting a Church decree of nullity. The couple might also find a divorce cheaper and easier to obtain that a civil annulment, and with the same end. So the fact that a couple can get a Church annulment but not a civil one, or vice versa, doesn’t mean anything. The laws used to decide each are totally different.
As noted above, a null or invalid marriage is one in which the Church finds an impediment preventing a valid marriage existed from the beginning. Because of that, there is no “statute of limitations” for those seeking a decree of nullity. Also, the Church presumes all marriages are valid until proven otherwise. This confuses some people, because they don’t understand how a couple who have been married 20-30 years can get an annulment. The answer is that there is a presumption of validity until a couple actually obtains a civil divorce and one of them asks for an investigation into the matter by the Church.
The process usually requires witnesses, so it is sometimes easier to do earlier rather than later. If a couple gets a civil divorce and one of them believes the marriage to have been invalid, that is a good reason to have the investigation done, even if re-marriage isn’t believed to be on the horizon. It may be difficult to find the necessary evidence of nullity later, should re-marriage be sought.
It is also allowed, though, for a couple in a valid marriage to obtain a civil divorce, if the reasons are serious…for instance, in order to fairly distribute goods and otherwise protect each spouse (or the children) when it is clear the couple cannot live peacably and in mutual safety in the same house. In this case, though, re-marriage is not allowed.
The choice to sin after marriage (infidelity or even abandonment, for instance) does not nullify a valid marriage, when the mutual intent and ability to fulfill the marriage vows were present at the beginning. Still, if the Church investigates and finds the marriage valid, the couple is not forced to try to reconcile, because the Church won’t investigate until it is satisfied that any attempt at reconcilation is either highly unlikely or is not prudent for some serious reason.
I hope that helps.
