Every time Karina Lorentzen from Socialistisk Folkeparti (SF) reads about a domestic homicide, such as the one that occurred Monday in Brønshøj, she thinks of a specific tool: the so-called reverse ankle monitor.

It is an ankle monitor, similar to the ones used for prison sentences. But instead of notifying authorities when a person leaves an area, in cases involving restraining orders, it alerts the probation service when a person is approaching someone they are legally required to stay away from.