The Metropolitan Police's Flying Squad had been tracking a gang of armed robbers from South London who were estimated to have stolen £500,000 (£876,000 today) from 18 robberies of security vans.
The Flying Squad received intelligence that the gang intended to target the HSBC branch in Chandler's Ford and planned to lie in wait and apprehend the suspects as they attempted the robbery.
Armed police officers arrived in Chandler's Ford in the early hours of the morning of 13 September and concealed themselves in a public toilet close to the bank, supported by snipers in overlooking buildings.
At 10:05, shortly after the arrival of the G4S van, Mark Nunes (wearing a mask) approached the guard and pointed a gun at him, demanding he hand over the cash box.
At the trial of the remaining gang members, the jury was shown footage from a police surveillance post at Chandler's Ford, including the moment Nunes and Markland were shot.
The shooting was investigated by the Independent Police Complaints Commission (IPCC), which concluded that the armed officers had acted properly, though it found flaws in the planning of the operation.
An inquest held in 2011 reached a verdict of lawful killing, after which the IPCC published its full report, recommending that a firearms commander independent of the investigation be appointed to lead future operations.
[3] In the 18 months prior to September 2007, the gang had targeted banks in small towns and villages in the home counties and some further afield, where they anticipated that the police response would be slower and more limited than in London.
[6][7][8] The Flying Squad received intelligence that the gang intended to rob a cash-in-transit van operated by the security services company G4S as it made a delivery to a HSBC bank branch in Chandler's Ford, Hampshire.
[10][11] In the early hours of 13 September 2007, Flying Squad and CO19 officers attended a briefing at Leman Street police station in East London before travelling to Chandler's Ford, arriving at around 04:00.
[12][16][17][18] During the trial, the jury was shown a video of the Chandler's Ford attempted robbery taken by police officers from one of the snipers' posts, including the moments Nunes and Markland were shot.
It found that, "although there are issues around the implementation of the operation", the police marksmen had not committed any misconduct, and had acted properly, in line with national guidelines for the conduct of armed officers.
[31][32] The Metropolitan Police issued a statement saying, "These circumstances illustrate clearly the immensely difficult and split-second decisions that officers have to make when protecting the public from the actions of armed criminals" and promised to review the findings of the inquest and the IPCC.
The academics observed that, unlike in other incidents they studied, the police appeared to have shot the "right" men, in so far as the only people killed were armed criminals in the commission of a robbery.
Nonetheless, they pointed out that the operation could only be seen as a "qualified success", given that its stated objectives included the apprehension of the suspects, and observed that the security guard could easily have sustained much more serious injuries.
In all three incidents, the police had intelligence that a crime was going to be committed but allowed events to proceed in order to gather evidence, resulting in dangerous confrontations (both Nicholas and Rodney were killed), rather than intervene at an earlier point and arrest the suspects safely but potentially jeopardise an investigation.