In some jurisdictions there is a concept of what is called separation under one roof. This means that it is still possible for a couple who are separating to be considered separated even if they remain living under one roof. Long before there was any specific statute regarding this the common law recognised that desertion in a marriage was not the withdrawal from the location of the marriage but the withdrawal from the emotional or relational elements of the relationship. Having laid down that proposition, the law was launched on a development which pointed to desertion as a legal fiction, with divorce for incompatibility as the ultimate solution to marital disintegration.
In the evolution of the law of marriage, such a development logically inevitable. Given that marriage is based and can legally only be based upon the free consent of both parties once the consent of even one of them is withdrawn the basis of the marriage disappears. The difficulty was always the need to uphold the family and to provide for children and the economically weaker partner of a broken marriage, usually the woman. The notion of separation under the same roof was thus hedged with restrictions requiring it to be clearly demonstrable. In England a test was evolved which became known as the two household tests.
According to the test, separation could occur under one roof where two spouses had continued to live under the same roof if there were such a forsaking and abandonment by one spouse of the other that the court could say that the spouses were living separately under one roof. This test proved to be rigid and unrealistic and it failed to reflect the relationship between former partners to a marriage who were not necessarily bitter enemies. When two people live in the same house where they cannot help seeing each other from time to time, it is unusually artificial for them to pretend that the other doesn’t exist. This is especially true when the couple have children living with them.
The English courts applied the view of the outsider rather than seeking to inquire more closely into the essence of the marital relationship itself. This it is questionable whether the test can ever answer the central question whether the conrtium has been broken or abandoned. Later in various states in the United States there were statutes enacted which said that it was not necessarily the case that being separated under one roof is not necessarily preclusive of the argument that there has been no separation.