Image copyright Yong Srey Pov Image caption Sam Yin (pictured far left) is remembered by her friends for her gentleness

Earlier this year, karaoke parlour singer, Sam Yin, 29, was shot dead by a police officer.

The officer escaped - but then resurfaced in August as a free man. He had reached a deal, it was reported, with the court, which closed the case after he paid $1,500 (£960) to Sam Yin's relatives.

"I heard about the compensation, but I can't confirm it," Takeo province's deputy police chief Suon Phon said in September.

Officers could only be dispatched to apprehend the suspected killer when the court issued an arrest warrant, the deputy police chief said, adding this week that he has yet to receive one.

"I don't know what happened because everything has been done at the provincial court."

In Cambodia, a small cash payment is often the most people can hope for when the rich and powerful are involved - and cases such as Sam Yin are far from unique.

Most policemen don't do anything... Some, when they are drunk, are very noisy and a little crazy Lak Youry, Cambodian singer

Shootings of women in Cambodia's entertainment sector were so frequent in 2006 that an opposition MP wrote to the defence and interior ministries demanding prosecutions.

In the weeks prior to his letter, police officers and soldiers had shot and wounded three beer promotion workers and a karaoke singer in separate incidents.

In one of those cases, a soldier shot a woman because she was too slow to bring ice for his drink.

Responding at the time, Defence Minister Tea Banh said the incident had been dealt with.

"Both the victim and my officials have a mutual understanding," he told a local newspaper, using the euphemism for paying cash compensation to circumvent justice.

'Gentle' friend

On a quiet Sunday morning in Takeo town, singer Lak Youry has a few hours free before returning to work at the karaoke parlour where she worked with Sam Yin.

Image copyright Van Roeun Image caption This was where Sam Yin had lived before she was shot dead earlier this year

Sam Yin "was very gentle", the 22-year-old said, recounting how they had gone to the beach the day her friend was killed.

The police officer, Sin Pov, 48, was furious that Sam Yin, his mistress, had gone on the day trip without his permission.

Three witnesses told of seeing the officer kick at the metal door to the tiny concrete room where Sam Yin lived with her 10-year-old son.

It is the fault of individuals; the government does not allow it to happen Lt-Gen Kirth Chantharith , National Police spokesman

Sam Yin would not unlock the door until the officer cooled down. He stopped kicking. She unbolted the door and within seconds there was a gunshot.

The office was last seen walking from the room, getting on his police motorcycle and driving away.

Lak Youry said that authorities with guns were part of the karaoke scene.

"Most policemen don't do anything. They just have their guns but don't take them out. Some, when they are drunk, are very noisy and a little crazy," she said.

A touch of fear, and keeping it under control, was part of the job, added Yong Srey Pov, 25, another singer.

Escaping justice?

Impunity enjoyed by the rich and powerful helps explain a lack of public trust in Cambodia's judicial and law enforcement institutions.

Image copyright Getty Images Image caption There is a lack of public trust in Cambodia's law and judicial bodies

Anti-corruption monitor Transparency International reported in 2013 that Cambodia's judiciary "was perceived to be the most corrupt institution out of 12 public institutions reviewed".

Police officers fared no better. Bribery of officers was "widespread across the country," Transparency reported, noting that 65% of respondents reported paying a police office a bribe in the previous 12 months.

In a 24 September statement to the UN Human Rights Council in Geneva, UN human rights envoy to Cambodia Surya Subedi said the list of impunity cases was "long and growing".

"Little has been done to bring perpetrators to justice," he said.

It is not just the rural karaoke clubs that are affected - famous entertainers have also been targeted.

Cambodia's Royal Ballet star Piseth Pilika was shot and killed in 1999.

In 2003, popular singer Touch Srey Nich was left paralysed after a shooting attack that also killed her mother. Another singer, Pov Panhapich, was left paralysed by a gunman's bullets in 2007.

Image copyright AFP Image caption Cambodian singer Pov Panhapich was left paralysed after she was shot by a gunman in 2007

No one has ever been held accountable for the attacks, which police commonly attribute to "revenge".

Among the public, rumours swirl of political motives or affairs with powerful officials and retribution by their vengeful wives.

More widely, a list of impunity cases should also include garment factory protesters killed by the security forces earlier this year, victims of a grenade attack on an opposition party rally in 1997, widespread land grabbing from the poor, and victims of hit-and-runs involving the rich and connected.

'No justice'

National Police spokesman Lieutenant General Kirth Chantharith denies there is a culture of impunity in Cambodia.

There is no real avenue for Cambodian victims to obtain fair and meaningful justice in Cambodian courts when cases are brought against the ruling elite Richard Rogers, British lawyer

"'Culture' means everybody is happy to do it. It means the police and the court like to do it," he said. "I accept it is happening. But it is the fault of individuals. The government does not allow it to happen."

Sar Mora, president of the Cambodia Food and Service Workers' Federation, has set up a hotline workers in the entertainment sector can call for help after an incident.

The union helps to prepare complaints for prosecution - but often that is as far as it goes, because the victims do not want to take on the rich.

"They do not believe or trust that they will get justice," he said. "They just accept money and go away."

British lawyer Richard J. Rogers is now seeking to internationalise the issue of impunity. He has asked the International Criminal Court to investigate Cambodia's "ruling elite", alleging "systematic land grabbing" over 14 years that has "adversely affected" some 770,000 Cambodians.

Government officials have dismissed the complaint, saying the figures are inaccurate and the facts erroneous.

Mr Rogers said the ICC "is the Cambodian people's last resort to obtain justice and escape the cycle of human rights abuses and impunity".

"There is no real avenue for Cambodian victims to obtain fair and meaningful justice in Cambodian courts when cases are brought against the ruling elite," he said.

Chhai Veasna, 45, who lives a few doors from the room where Sam Yin was killed in March, agreed.

"If I can say it bluntly: there is no justice," he said. "We feel very sorry that the woman was killed and [the police officer] got away free."

(Additional reporting by Van Roeun and Phorn Bopha)