This is a fascinating case. Sometimes victims of DV can have a 'panic room' installed in their home which is a secure room they can hide in which is only lockable from the inside in the event of their abuser attempting to break in and attack them. This woman has fallen foul of the 'bedroom tax ' because of this extra room. It's just another example of how different people can fall foul of this unjust law. I hope she wins her case.
www.theguardian.com/society/2014/nov/18/panic-room-woman-challenges-bedroom-tax