The Metropolitan Police force has defended the actions of its armed officers ahead of a Panorama TV show about police tactics, due to be aired tonight (Monday).
The documentary called "Shoot to Kill?" comes in the wake of a court case on Mark Duggan earlier this month, when a jury decided he was lawfully killed.
Members of the police unit which shot dead Duggan are interviewed by Panorama as the programme scrutinises police tactics.
Scotland Yard admitted it had been a mistake to not review its tactic of using police vehicles to force another vehicle to halt – known as an enforced or hard stop.
An investigation into hard stop tactics was recommended by the Independent Police Complaints Commission following the death of Azelle Rodney, who was shot dead by Metropolitan Police officers in 2005.
A Scotland Yard spokesman said: "Firearms operations against the most dangerous and determined armed criminals are of course not straightforward. We are proud of our success in reducing gun crime in London by taking weapons off the street and putting criminals in prison for long periods.
"Criticising those who have the responsibility for running such challenging operations is easy. We welcome better ideas and are currently researching internationally to see if other forces have alternative tactics."
Armed police attend 3,000 firearms incidents each year in London and carry out an additional 1,200 planned incidents.
A police spokesman said officers fired their weapons "only once or twice a year." Some 50 people were shot dead in London since late 2008. The number has been declining.
"We do many hundreds of these operations a year and it is extremely rare for shots to be fired. This is because of the professionalism, training and restraint of armed officers.
The alternative to using this tactic is to allow highly dangerous criminals who get into cars with guns intent on committing harm to carry out the crime, only investigating it afterwards, with potentially catastrophic consequences for their target, said police.
"Alternatively we could intervene early and disrupt the crime but this may fail to gain sufficient evidence to prosecute them. They will then go free to plan more criminality but now they will be forewarned," added the spokesman.
Sophie Khan, legal director at the Police Action Centre pressure group, told IBTimes UK: "The reforms that need to be considered are about hard stops and the information the police have on the person who they want to stop because when things go wrong, they go badly wrong.
"The Mark Duggan case returned a verdict of lawful killing, but this could be different in another case. But there are other priorities such as the use of Tasers and stop and search. There are concerns about training here."