Plans to protect the Houses of Parliament at Westminster include the use of attack dogs. In a review of perimeter security, Sir Paul Beresford, former chairman of the Commons administration committee believes that attack dogs could stop a terrorist without endangering members of the public.
"If we'd had a dog there PC Palmer might have been saved," he said in a Sunday Times report.
He said: "If some idiot, who is not a terrorist, runs in, and there are a few of those out there, the dog will drop them and they won't be shot."
He added: "The gates have to be open when MPs are coming in to vote, but we recognise it is a chink in the armour." Beresford said the deployment of dogs was being "seriously considered".
Other preventative measures are stronger vehicle barriers, while a second inquiry will look into security inside the building.
A Parliamentary spokesperson said: "Two reviews have now been commissioned into the perimeter security at Parliament and into the Houses' response following the incident on 22 March.
"Both reviews have encouraged and sought the views of those on the estate on that day and from the public. This feedback will be considered in detail along with other evidence."
The police dogs are already part of security arrangements and used at British military bases. The dogs are trained to respond to particular acts or commands and are used to enforce public order by chasing and detaining suspects by a method known as "bark and hold". The German Shepherd is still the preferred breed with the British police and armed forces.
But there are fears that these dogs will attack members of the public. A BBC report found that UK police forces paid out £120,000 in compensation between 2011 and 2013. Some forces refused to reveal how much money had been paid on grounds of "confidentiality".