It is my understanding that anyone officiating a wedding ceremony must be licensed by the state/province in which the ceremony is to be performed. Even if the officiate is a Minister or Clergyman, he/she must be licensed by the state. Perhaps the requirements differ in each state as to who may be automatically qualified.
minimus, when you said:
It's been a long time since I married a couple as an elder, over a decade ago. It was always in massachusetts.
where you actually recognised (licensed) by the State of Massachusetts or did you proceed only due to being a JW Elder?
I have known very few JW Elders who were licensed to perform weddings.
When you think of weddings, they are actually civil matters with regards to legality and recognition by the government although the ceremony is often performed as a semi religious ceremony. Some people prefer a non-religious ceremony so they utilize a Justice of the Peace or other layperson to marry them.
If weddings were truly religious in nature, much like prior baptism by another denomination, I'm certain that the WT would require all newly converted JW couples to be remarried in a WT dictated ceremony.