By Bill Law
BBC News, Manama
Authorities in the Gulf island kingdom of Bahrain say they have undertaken a lengthy list of reforms of the police but critics say the reforms are little more than window dressing.
The police were heavily criticised in November 2011 by a panel of international human rights experts for the brutality with which they had put down anti-government unrest earlier that year.
Dozens died, hundreds were injured and hundreds more arrested - almost all Shia Muslims, the majority population in a country ruled by a Sunni Muslim royal family, the al-Khalifas.
The Bahrain Independent Commission of Inquiry (BICI), established by King Hamad al-Khalifa in response to an international outcry, delivered a damning verdict.
The report found the police responsible for nine deaths which "resulted from the use of excessive and unnecessary lethal force".
It found that a further five people died as a result of torture while in police custody.
In response, amongst other initiatives, the government set up a Special Investigations Unit to investigate police wrongdoing, established the position of police ombudsman and installed video cameras in every interview room.
However opponents of the government say that even after the release of the BICI report police continue to behave with impunity.
International human rights organisations and al-Wefaq, the main opposition party in Bahrain, have documented further deaths in custody, the excessive use of tear gas and birdshot, arbitrary arrests and abuse in detention.
Tarik al-Hassan, Bahrain's chief of police, rejects much of the criticism, noting that the police are frequently under assault from petrol bombs and other homemade weapons.
In early July an officer was killed when a homemade bomb exploded.
"The reform of the police in Bahrain have gone beyond the requirements of the BICI," he told the BBC.
"You will find that all interview rooms have been fitted with video and audio recording and you know there is still room for improvement. It is not something that we will say it is done and that's it."
And the country's Justice Minister Sheikh Khalid al-Khalifa said "the end-game is to have a culture change, to end the culture of impunity, if it exists."
But the BBC uncovered evidence that challenges the government's assurances.
It is a video filmed by an officer in June of this year in a police station and posted on his Facebook site. Shot close-up, it shows a young Shia being interrogated. He is shirtless and appears terrified.
He confesses to being paid 10 Bahraini dinar ($30) a day, by two senior Shia clerics to attack and kill police officers.
As the video ends and he stands up, a deep wound is visible on his left shoulder.
The video proved an embarrassment to the police. It was quickly removed and the officer was arrested.
However Mr Marhoon, despite the evidence of a confession extracted under duress, remained in jail more than two weeks after the incident happened.
"Well," he replied, "that was not in the interview room. That was in the corridor and now we have a plan to have all corridors fixed with CCTV."
The chief said he was outraged by the video: "It does not represent our principles, it does not represent what we stand for."
That is a view the opposition does not share.
The Bahrain Centre for Human Rights (BCHR) released a report called "Five Days in Bahrain" in late July.
The centre documented what it called "60 cases of illegal arrests, 140 shotgun injuries, and over 150 house raids in just the last five days".
BCHR said the majority of arrests occurred "after policemen, accompanied by masked civilians, raided individuals houses without an arrest warrant".
It reported one youth seriously wounded with birdshot while participating in what it called a peaceful demonstration.Chance for change?
These kinds of allegations and the abuse of Hussein Ali Marhoon are what the police ombudsman Nawaf Almaawdah told the BBC he will investigate.
Mr Almaawdah has the opportunity to have a huge impact on how the police behave and how they are perceived by the Shia community, if he is allowed to.
He was shown the video and said: "This is unacceptable and we are keeping a close eye on this case."
But he was unable to say if Mr Marhoon, a victim of police abuse, had been visited by anyone in his office.
That in itself raises questions about how effective the ombudsman will be.
When asked how he responded to criticism that the post was little more than window dressing, M. Almaawdah replied: "Wait for our public report and give us the chance to progress in this office."
But in the Shia villages where anger against the police runs deep very few people are prepared to give the ombudsman, or indeed the government any chance at all.
As one government opponent commented: "There is a big difference between what they say and what they do on the ground. They can say whatever they want. But in reality what happened? They are just good at talking."