Two of the dangerous dogs seized by Merseyside Police in January 2007
The death of four year old John Paul Massey in Liverpool following an attack by a 'pitbull terrier type' dog in November 2009 once again highlighted the issue of dog attacks.
John Paul Massey died from head and neck injuries after being attacked by the dog at his grandmother's home in Wavertree.
The dog was later shot dead by armed police officers.
John Paul's death had echoes of that of five year old Ellie Lawrenson in St Helens in 2007.
BBC Radio Merseyside 95.8FM held a special debate on Dangerous Dogs.
Listen to the programme
If the dogs are banned why are there still attacks?
The Dangerous Dogs Act 1991 bans the breeding, sale or exchange of four kinds of dogs: pit bull terriers, Japanese tosas, the dogo Argentinos and the fila brasileiros.
Four year old John Paul Massey was killed by a dog in Wavertree in 2009
Cross-breeds of these are also covered by the law. Other dogs that appear bred for fighting are also banned, however some dogs can be legally held under an exemption.
A dog classed as dangerously out of control in a public place can be destroyed and the owner fined or jailed for up to six months.
Owners can be imprisoned for a maximum of two years if their dog injures someone.
In the late 1990s the law was amended to give courts the power to allow owners to keep pitbulls if it can be proved the dog is not a danger to the public.
There are stringent conditions attached to this such as having the dog neutered, microchipped and insured - as well as being kept on a lead and muzzled in public.
In Merseyside this exemption now applies to more than 150 pitbulls. Nationally there is a total of 832 dogs on this list.
The growth in this 'exemption list' has been increased in recent years. In 2005 there was only one dog on the national list. In 2007, 185 dogs were added and in 2009, 396 dogs were put on the list.
Do police act to remove dangerous dogs?
Following an attack in St Helens which resulted in the death of a five year old girl in 2007 Merseyside Police acted to crack down on the number of dangerous dogs.
Ellie Lawrenson died of severe head and neck injuries after being mauled at her grandmother's house in St Helens by a pit bull terrier on New Years Day 2007.
After her death Merseyside Police introduced a dog amnesty for owners to hand in illegal dogs.
Around 200 dogs were received by the force and they seized many others.
How many dog attacks are there on Merseyside?
In 2009 Merseyside hospitals treated 1534 people following dog attacks - which works out at around 30 people a week attending hospital accident and emergency after being attacked by dogs.
Southport and Ormskirk Hospitals treated 441 people as the result of dog attacks in 2009, 363 people were treated at Arrowe Park, and 463 in Warrington and Halton.
At Whiston hospital the number of cases has doubled in just under ten years from 60 in 2000 to 175 in 2009. The largest rises were in attacks on children under the age of 10 and adults aged between 40-45. Registrars at the hospital found that status dogs including pitbull and rottweiler were to blame for the majority of the attacks.
How do you tell if a dog is a dangerous dog?
It's not easy, particularly with pitbulls.
Police need a team of experts who know the characteristics of pitbull terriers and are able to make an assessment of whether a dog is an illegal type.
When a case comes to court police need to be sure they can prove a dog is an illegal breed.
Merseyside Police often employ freelance experts to back up their case, former Metropolitan Police dog handler Peter Tallack is one of the professionals the force employs, he says the definition of what is a pitbull can make it difficult to distinguish what is a dangerous dog.
"They're a functional dog, and that's what makes them attractive," Peter Tallack told BBC Radio Merseyside.
"They're fit, they're quick, they're intelligent.
"The standard for a pitbull that was written back in 1977 has no mention of colour, so a pitbull can be any colour, there's no mention of height or weight because historically they were thought of as boxers and there's no mention of the ears."
There is a 30 minute documentary on BBC Radio Merseyside on Friday 2 April 2010 at 1830BST looking at the issue of dangerous dogs in Merseyside.