The two men have denied the charges against them
Two of England's most senior policemen have gone on trial accused of failing to protect their officers from harm.
Metropolitan Police Commissioner Sir John Stevens and his predecessor, Lord Condon, who retired in January 2000 appeared at the Old Bailey on Wednesday.
The trial follows the death of Pc Kulwant Sidhu and injuries to Pc Mark Berwick after they fell through the roofs of two separate buildings while chasing suspects.
Both Sir John and Lord Condon have pleaded not guilty to four charges under the 1974 Health and Safety at Work Act.
Prosecutor William Norris QC told the Old Bailey such prosecutions were usually brought against a company.
But Parliament had decided that, in the case of police, the chief officer had to be prosecuted personally if there was any alleged breach.
Those responsible for health and safety at the Met had no proper system in place at the time at all
Prosecutor William Norris QC
He said the commissioner had many responsibilities but these included the health and safety of his officers.
"Putting it bluntly, the buck stops with them," said Mr Norris.
"This is a failure of the Metropolitan Police for which they, at the relevant time, were responsible. The failure of
the Met to manage issues of health and safety properly."
He said the prosecution said officers should only go up on roofs when "strictly necessary" and should not just be allowed to act on their own initiative.
Roofs 'potentially lethal'
"If police officers were to make a judgment on whether to go on a roof they need to know that every roof should be treated as potentially lethal," said Mr Norris.
"Those responsible for health and safety at the Met had no proper system in place at the time at all."
The court heard there were 69 cases of Met officers falling from heights between June and November 2000, with 16 in November alone.
Sir John wore full uniform and Lord Condon was dressed in a suit as they sat side by side opposite the jury.
They have been told they need only attend court when essential.
Mr Justice Crane told the jury: "It would be contrary to public interest for them to sit in court the whole time. They must have regard to their other commitments."
The trial continues.