Deceased Wife's Sister's Marriage Act 1907

The Deceased Wife's Sister's Marriage Act 1907 (7 Edw.7 c.47) was an Act of the Parliament of the United Kingdom, allowing a man to marry his dead wife's sister, which had previously been forbidden. This prohibition had derived from a doctrine of canon law whereby those who were connected by marriage were regarded as being related to each other in a way which made marriage between them improper.

The doctrine that such marriages were illicit was reflected in the Table of kindred and affinity in the Anglican (Church of England) Book of Common Prayer. Prohibition of marriage between certain degrees of kindred outlawed what is known as incest; prohibition between degrees of relationship by marriage (affinity) as opposed to blood (consanguinity) seems to have reflected an analogous taboo. At least one novel, Felicia Skene's The Inheritance of Evil (1849), addressed the topic in polemic fictional form.

Under ecclesiastical law, a marriage within the prohibited degrees was not absolutely void but it was voidable at the suit of any interested party. Matthew Boulton married his deceased wife's sister in 1760. He advised silence, secrecy and Scotland, although they married in London; the marriage was opposed by her brother. Similarly Charles Austen, the younger brother of Jane Austen, married his deceased wife's sister in 1820 and remained married to her until he died in 1852.

The Marriage Act 1835 (5&6 Will.4 c.54), however, hardened the law into an absolute prohibition (whilst, however, validating any such marriages which had already taken place), so that such marriages could no longer take place in the United Kingdom and colonies at all (in Scotland they were prohibited by a Scottish Marriage Act of 1567). Such marriages from that date had to take place abroad: see, for example, William Holman Hunt and John Collier, both painters, who married the sisters of their deceased wives in Switzerland and in Norway respectively. However, this was only possible for those who could afford it.

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