Young and Willmott - Argue that men are now taking on a greater share of domestic tasks and more wives becoming wage earners.
Feminists - Reject Parson's view that the division of labour is natural.
1: Victims may be unwilling to report it to the police. Research shows a woman suffers 35 assaults before making a report.
2: Police and prosecutors may be reluctant to record, investigate or prosecute those cases that are reported to them.