Domestic Violence and Matrimonial Proceedings Act 1976 as new law
In a judgment (speech in House of Lords) in Davis v Johnson (9 March 1978; )  UKHL 1,  AC 264 at 348 Lord Scarman explained the remedies provided by Domestic Violence and Matrimonial Proceedings Act 1976 (DVMPA 1976) s 1; and then, he defined domestic violence for the purposes of the Act:
… Conduct by a family partner which puts at risk the security, or sense of security, of the other partner in the home. Physical violence, or the threat of it, is clearly within the mischief. But there is more to it than that. Homelessness can be as great a threat as physical violence to the security of a woman (or man) and her children. Eviction — actual, attempted or threatened — is, therefore, within the mischief: likewise, conduct which makes it impossible or intolerable, as in the present case, for the other partner, or the children, to remain at home.
Lord Scarman was a pre-eminent family lawyer from a time when children law was hardly regarded as a separate discipline (think Re F (orse A) (a Minor) (Publication of Information)  Fam 58,  3 WLR 813, CA; A v Liverpool City Council  AC 363,  2 WLR 948, (1981) 2 FLR 222; Gillick v West Norfolk and Wisbech AHA  UKHL 7,  1 AC 112,  1 FLR 224; Re E (A Minor) (Wardship: Court’s Duty)  FLR 457 for a flavour of his children law work).
Non-molestation orders: a new family law remedy
Before the quote above, Lord Scarman (who gave the fifth speech) had set out the text of s 1(1) of the Act (still no mention of domestic violence or domestic abuse – just of ‘molesting’ a party:
(1) Without prejudice to the jurisdiction of the High Court, on an application by a party to a marriage a county court shall have jurisdiction to grant an injunction containing one or more of the following provisions, namely—
(a) a provision restraining the other party to the marriage from molesting the applicant;
(b) a provision restraining the other party from molesting a child living with the applicant;
(c) a provision excluding the other party from the matrimonial home or a part of the matrimonial home or from a specified area in which the matrimonial home is included;
(d) a provision requiring the other party to permit the applicant to enter and remain in the matrimonial home or a part of the matrimonial home, whether or not any other relief is sought in the proceedings
Lord Scarman explained s 1(1) as follows:
Subsection (1) enables a party to a marriage to make application to a county court. It is without prejudice to the jurisdiction of the High Court and it empowers a county court (any county court, whether or not invested with divorce jurisdiction) to grant an injunction “whether or not any other relief is sought.” Clearly the subsection provides a new remedy additional to, but not in substitution for, what already exists in the law.
Section 1(2) applied s 1(1) equally to a couple who were not married; and references to matrimonial home were to be construed accordingly.
Non-molestation in 1996; but still no domestic violence definition
And so, in 1975-6, a new family law remedy was born in the 1976 Act. It was intended to cover both the married and the unmarried, and their children: the free-standing (‘whether or not any other relief is sought’) non-molestation injunction. This is the remedy which – for today’s purposes – is reproduced in Family Law Act 1996 s 42(1):
42 Non-molestation orders
(1)In this Part a “non-molestation order” means an order containing either or both of the following provisions—
(a)provision prohibiting a person ( “the respondent”) from molesting another person who is associated with the respondent;
(b)provision prohibiting the respondent from molesting a relevant child.
The 1996 still avoided a definition of ‘domestic violence’: the rest of s 42 deals with procedural matters; whilst earlier sections of FLA 1996 had dealt with occupation orders.
The charming authors of Legal Aid Sentencing and Punishment of Offenders Act 2012 attempted a definition of ‘domestic violence’ which is tucked away at Sch 1 para 12(9):
‘domestic violence’ means any incident, or pattern of incidents, of controlling, coercive or threatening behaviour, violence or abuse (whether psychological, physical, sexual, financial or emotional) between individuals who are associated with each other;…
Contact practice direction and domestic abuse
In Family Procedure Rules 2010 PD12J Child Arrangements & Contact Orders: Domestic Violence and Harm those who draft Family Procedure Rules 2010 and their accompanying practice directions have given us as a definition of domestic abuse – but only in relation to child contact. Para 4 (I set this out in full):
‘domestic abuse includes any incident or pattern of incidents of controlling, coercive or threatening behaviour, violence or abuse between those aged 16 or over who are or have been intimate partners or family members regardless of gender or sexuality. This can encompass, but is not limited to, psychological, physical, sexual, financial, or emotional abuse. Domestic abuse also includes culturally specific forms of abuse including, but not limited to, forced marriage, honour-based violence, dowry-related abuse and transnational marriage abandonment;…
In addition the terms ‘abandonment’, coercive behaviour’, controlling behaviour’ and ‘ill-treatment’ are further defined.
A practice direction as law
The first comment on this must be to recall that a rule, still less a practice direction, cannot change the law (Re Grosvenor Hotel, London (No 2)  Ch 1210, CA approved by Supreme Court in Dunhill v Burgin (Nos 1 and 2)  UKSC 18,  1 WLR 933 at ). The law is what was explained by Lord Scarman in Davis v Johnson. And anyway what does the practice direction add to what was said by Lord Scarman 40 years ago?
One problem with any definition is that the more extensive you make it, the weaker it is: detail only suggests more ways in which a person can wriggle round it. That is the beauty of Lord Scarman’s definition; and as law it applies to a much wider set of statutory circumstances (FLA 1996 s 42; children proceedings generally (ie not only contact); and occupation orders).
The practice direction is a lesser form of law, and priority when advice is given or legal aid applied for, should be given to Lord Scarman (with a nod, perhaps, to LASPOA 2012 Sch 1).