Cameron is critical of Klass ruling

Klass was warned by officers about waving a kitchen knife to scare off intruders who had entered the garden of her home near Potters Bar, Hertfordshire.

The Tory leader said that police "do seem to do things that slightly fly in the face of common sense".

Asked about the incident, he said: "If that is the case I think it is ridiculous to complain about someone who is obviously worried about what people were threatening her with.

"Sometimes the police do seem to do things that slightly fly in the face of common sense."

He went on: "I don't know the facts of the case and sometimes when you look at these cases and you find a bit more detail, you find it is not quite ... what it appears.

"But we want some common sense in policing. One of the things that has gone wrong with all this red tape and form filling is that we are taking away discretion from the nurse, the teacher, the doctor, the police officer. We have got to give them back that discretion."

Klass, who was at home with her daughter on Friday at the time of the incident, has said she has "no regrets" at doing "what any other mother would do".