You are not legally married if you have no marraige license. They must immediately go to the nearest town clerk and get the license.
The above is a general answer and is not considered legal advice. You should contact an attorney before proceeding to take any legal action, signing any papers or upon service of a summons.
You did not indicate where the couple resided following the religious marriage 18 years ago. It could make a difference if that place was somewhere other than New York. New York State has long refused to recognize common-law marriages. The state statutorily abolished common law marriage in 1933 by enactment of section 11 of the Domestic Relations Law. New York courts, however, do recognize common law marriages in other states. In determining whether a common-law marriage exists under the laws of another state, the New York courts must make detailed factual findings about a couple's personal lives.
If the couple has resided in New York for their entire marriage, then I must agree with Attorney Knispel. They should get a license and renew their vows. They can even use it as an occasion to celebrate their enduring love for one another.
I assume you are referring to a NYS marriage. Despite the lack of a marriage license, you are validly married per Domestic Relations Law section 25. This further assumes that you marriage was not void when you got married for other reasons. Further, depending upon your situation, there is always the possibility that the marriage is voidable. The can always be remarried now with a license if they wish to be secure at a city ceremony, for example. For most of the items you mention, marriage will not have an effect, though it may with others. Your friend should consult a matrimonial/estate planning attorney.
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