LONDON — Lawmakers on the island of Jersey have approved scrapping a decades-old law that prevented married women from talking to the tax authorities without the permission of their husband or filing taxes under their own names, a mechanism described by a local senator as “archaic.”

Jersey, a small island in the English Channel a few miles from the French coast, is a dependency of the British crown but is by and large independent of Britain, with its own directly elected assemblies, fiscal system and courts.

That distinction has made Jersey a popular tax haven, but its financial laws have not always kept up with the times: Under its current tax law, introduced in 1928, only the husband in a heterosexual marriage can pay taxes, with his wife’s earnings considered part of his income. She has needed his permission to be treated separately or even to discuss her financial affairs with the tax office.

Things became a bit more modern in 2013, when a box appeared on income tax forms that husbands could tick rather than giving written permission.