Los Angeles police landmarks

1922: Louis Oaks, a Ku Klux Klan member, becomes LAPD chief. 1965: Watts riot 1971: Crips formed in South Central LA. 1972: Bloods formed to challenge dominance of the Crips 1991: Rodney King beaten 1992: 54 killed in riots sparked by acquittal of Rodney King police officers 1995: O J Simpson acquitted after jury hears of police misconduct 1999: Rampart scandal breaks, eventually embroiling 70 officers 2002: Bill Bratton becomes chief of police

Bill Bratton clearly relishes a challenge.

The former New York police chief, who managed to halve the murder rate in the Big Apple, has now taken up the task of cleaning up Los Angeles.

But his new job is arguably much harder than his old one.

For starters, New York had 40,000 officers while Los Angeles, albeit with only half the population, has only 9,000.

Secondly the LAPD has a dreadful reputation for police brutality - the Rodney King affair was only the tip of the iceberg - and widespread corruption.

The hit TV show The Shield was based on the LAPD's Rampart scandal and actor Michael Chiklis won an Emmy for playing Vic Mackey, a policeman who plants guns on suspects, takes pay-offs from drug dealers and even kills a fellow officer who has been asked to uncover these dirty dealings.

Perhaps the biggest obstacle Mr Bratton faces is the gang violence that is endemic in Los Angeles in a way it has never been on the East Coast.

This year there have been 656 murders in LA, up from 552 last year.

Rodney King, beaten up by police, was awarded $3.8m

Six out of ten were gang-related and 115 were committed across a neighbourhood of 12 square miles known as South Central.

One of Mr Bratton's first actions was to appoint a new deputy to oversee anti-gang efforts.

He also ordered graffiti - widely used by the gangs to mark their territory and insult their rivals - to be cleaned off the city's walls.

Murders in 2002

Los Angeles: 656 New York: 575 London: 118 (excluding December) West Midlands: 48 (Apr 2001-Apr 2002)

This was an extension of the "broken window" theory - that vandalism should be repaired as soon as possible to prevent communities deteriorating - which worked so well in New York.

'Terrorists'

Mr Bratton compared the gangs to terrorists and called on the federal authorities to use legislation used against the mafia to crack down on the gangs.

Many black and hispanic Angelenos find themselves between a rock and a hard place.

They detest the malevolent influence of the 500 street gangs - Bloods, Crips and others like the Latin Kings - but also resent the high-handed and allegedly racist manner of many LAPD officers.

The corrupt cops featured in The Shield are based on the Rampart scandal

One of Mr Bratton's hardest jobs will be to try to restore public confidence in his officers.

Mounting anger spilled over in 1992 following the acquittal of four officers caught on camera beating up black suspect Rodney King.

The riots that followed killed 54 people and caused $1bn worth of damage to Compton and other parts of South Central LA.

'Control your cops'

After a spate of recent shoot-outs, which led to the death of two Latino teenagers, demonstrators called on Mr Bratton to "control your cops".

He responded with characteristic gusto: "Control your kids!"

But it has been allegations of corruption that have been doing more harm to the LAPD's already tarnished reputation.

The founder of the Crips, Stanley "Tookie" Williams, is now on Death Row

There have been corruption scandals in LA since the 1940s - it is no coincidence crime writers Raymond Chandler and James Ellroy both used the city as a backdrop for tales of crooked cops.

But even hardened reporters were shocked when, in September 1999, an officer called Rafael Perez began to spill the beans on an affair that became known as the Rampart scandal because of the division in which he worked.

Perez, who was facing some serious jail time after being found to have stolen 6lb of cocaine from a police evidence locker, eventually embroiled 70 officers.

'Routinely planted evidence'

Many of them were in the Rampart division's elite anti-gang CRASH unit (Community Resources Against Street Hoodlums).

Perez claimed they shot unarmed civilians, routinely planted evidence, including guns, on suspects, beat others up, robbed banks, dealt drugs and lied in their police reports.

LAPD officer Brian Liddy explains a video which was shown to a jury in one of the Rampart trials

Five officers were fired and eight resigned but Perez's credibility as a witness was soon in doubt because of his own record of perjury.

Thom Mrozek, a spokesman for the US attorney's office in Los Angeles, told BBC News Online: "The federal investigation into allegations of misconduct in the Rampart Division CRASH unit has not yet concluded.

"There may be additional federal civil rights charges brought in the investigation."

Greg Boyle, a Jesuit priest who founded Homeboy Industries in 1988 in an attempt to wean young Angelenos off the gangs, was invited to talk to Mr Bratton last week.

Gang member Carlos Ortiz, 15, escaped from custody while awaiting a murder trial

He had been worried by his "declaring war on gangs" rhetoric but he said he had been very impressed by the new chief.

Father Boyle told BBC News Online: "He's a cop's cop but he's also an astute politician and a quick learner.

"He knows the lie of the land and he knows the landmines to avoid, such as racial profiling."

'No quick fix'

Father Boyle said Mr Bratton admitted there was no "quick fix" to Los Angeles' crime problems, or to the existence of the city's 300 or so gangs.

Graffiti denoting the Denver Lane Blood gang from downtown LA

He said: "He gives the impression that he is in it for the long-term and he wants to effect a revolution in police culture."

Father Boyle said Mr Bratton was a larger-than-life character but he said that might be a good thing: "He is just full of himself enough to have the ego to really do this.

Police union welcome

"All the signs are to something good, but, of course, he could turn out to be a disappointment."

The thing that's good about him is that... he remembers what it was like to be a police officer and he likes cops. Mitzi Grasso LA Police Protection League

Mitzi Grasso, vice president of the Los Angeles Police Protective League, said: "We love him. The thing that's good about him is that, unlike many of his predecessors, he remembers what it was like to be a police officer and he likes cops."

She said morale and productivity were both up since his appointment and arrests had risen by 50%.

Ms Grasso said: "We have a significant crime problem at the moment but we will be able to knock it down by mid-year."