“It is time for the Bahraini authorities to comply with the rights to peaceful assembly and expression and immediately release those arbitrarily detained for exercising their legitimate freedoms,” the experts said in a news release issued by the Office of the UN High Commissioner for Human Rights (OHCHR).

They also called for the immediate release of human rights defender Nabeel Rajab, who was convicted on three charges of illegal assembly related to his participation in peaceful gatherings in favour of fundamental freedoms and democracy, including a peaceful protest to denounce the detention of fellow defender Abdulhadi Al Khawaja. Rajab was recently sentenced to three years imprisonment.

Since February, there have been clashes in Bahrain between security forces and demonstrators, a year after widespread civil protests first emerged in the Gulf country.

“The sentencing of Nabeel Rajab represents yet another blatant attempt by the Government of Bahrain to silence those legitimately working to promote basic human rights,” said the Special Rapporteur on human rights defenders, Margaret Sekaggya.

“The Bahraini Government must immediately cease its campaign of persecution of human rights defenders in the country,” she added.

The Special Rapporteur on freedom of peaceful assembly and of association, Maina Kiai, stressed that “the exercise of the right to freedom of peaceful assembly should not be subject to prior authorization from the authorities.”

He noted that the criminalization of people participating in peaceful assemblies for the sole reason that they did not seek the approval of the authorities to hold such assemblies contradicts international human rights law.

Rajab is also currently serving three months imprisonment for alleged libel through a social networking site. After a series of postponements, a decision by Bahrain’s Higher Appeal Court on that sentence is reportedly due to be announced today.

“The continuing repression of free speech in Bahrain runs counter to international law and standards that individuals will not be prosecuted for peaceful political speech,” said the Special Rapporteur on the right to freedom of opinion and expression, Frank La Rue.

He added, “The authorities must take all measures to guarantee the free expression of all individuals in Bahrain, whether through social media or otherwise.”

Independent experts, or special rapporteurs, are appointed by the Geneva-based UN Human Rights Council to examine and report back on a country situation or a specific human rights theme. The positions are honorary and the experts are not UN staff, nor are they paid for their work.

Rajab was sentenced on August 16, 2012, to three years in prison for his involvement in three demonstrations between January and March 2012. Defense lawyers told Human Rights Watch that the judge issued the sentence before they could get to the hearing from a hearing in another case involving Rajab in another court. Rajab was taken to prison before he was able to meet with lawyers or his wife and children.

“This ruling shows that Bahrain’s rulers are committed to a policy of comprehensive repression,” said Joe Stork, deputy Middle East director at Human Rights Watch. “Instead of releasing people jailed for peaceful dissent, it seems determined to lock up even more people who try to exercise their right to peaceful assembly and free expression.”

A prosecution official had earlier told Bahraini media that Rajab had incited violence. But authorities have yet to provide, in court or anywhere else, any indication of what it was he said or did that constituted incitement, Human Rights Watch said.

Rajab was already serving a three-month prison term for allegedly “insulting” the people of Muharraq, a town outside of Manama, the capital. The conviction was based on Rajab’s June 2 tweet calling for the prime minister to resign, saying he was not popular in the town. Hours after that sentence was issued on July 9, masked security officers arrested Rajab at his home.

Defense lawyers Jalila Al-Sayed and Mohamed al-Jishi told Human Rights Watch that on August 16, they first attended an appeal session in a separate court regarding Rajab’s Twitter sentence. The hearing was adjourned until August 23. They went to the “illegal gathering” hearing immediately afterward. Before they arrived, though, they learned that the judge had already ruled on the case and that security officials had taken Rajab back to prison.

“Nabeel Rajab has committed no genuine criminal offense, to judge from everything Bahraini officials have said about the case, and now it is also clear that they also violated his right to a fair trial,” Stork said.

On August 12 the defense team filed a complaint with the Supreme Judicial Council requesting the replacement of the judge assigned to the “illegal assembly” hearing after he had earlier moved up the date of the session from September 26 without consultation or “reasonable cause,” the lawyers said. The Supreme Judicial Council did not respond to the complaint.

“Rajab is a human rights activist and he was just exercising his right to peaceful gathering and was calling for justice in this country,” al-Sayed told Human Rights Watch. “He was just expressing what most Bahrainis want to say but fear prosecution if they were to say it loudly.”

In a separate case, police stopped Said Yusif al-Muhafdah, a prominent activist with the Bahrain Center for Human Rights, when he was driving with his two young daughters on August 16. He told Human Rights Watch that the police said they had received a complaint from other police at a traffic checkpoint. When they searched his car they found a poster of Rajab and asked, “Who is this son of a bitch?” When al-Muhafdah objected, he said, the policemen struck him on the head and told him to phone his wife to pick up his daughters. They then took him to a police station for questioning before releasing him nearly three hours later. Al-Muhafdah told Human Rights Watch that he filed a complaint with the public prosecution today for mistreatment by the police.

The Obama administration should raise Rajab’s case forcefully with the Bahraini government, Human Rights Watch said.

Nabeel Rajab, the President of the Bahrain Centre for Human Rights, was arrested on 9 July, just hours after a court in the capital Manama sentenced him for libel following a complaint made against him by the people of al-Muharraq area, north of Bahrain, for “publicly vilifying the al-Muharraq people and questioning their patriotism with disgraceful expressions posted via social networking websites”.

“Nabeel Rajab’s imprisonment is the latest example of how, despite government promises to introduce reforms following its violent crackdown on protesters in 2011, few improvements have been seen on the ground. It’s clear that repression of freedom of expression is continuing with impunity in Bahrain,” said Ann Harrison, Amnesty International’s Middle East and North Africa Deputy Programme Director.

“Like many others in Bahrain, Nabeel Rajab is a prisoner of conscience, jailed solely for peacefully exercising his right to freedom of expression. He should be released immediately and all other charges or convictions against him dropped or overturned. The authorities must also act to ensure that all human rights defenders are able to carry out their work without fear of reprisal.”

The charges against Rajab related to a 2 June tweet addressing the Prime Minister, Shaikh Khalifa Bin Salman Al Khalifa, following his visit to the area. Rajab wrote: “Khalifa: Leave the al-Muharraq alley ways, their sheikhs and their elderly, everyone knows that you have no popularity there; and if it was not for their need for money they would not have come out to welcome you – when will you bow out?”

Rajab was arrested on 6 June following complaints about the tweet from several people of al-Muharraq. He was charged with libel on 14 June and released on bail on 27 June.

Rajab is now held in al-Jaw prison, in Manama. He has already served 21 days of his three-month sentence. His lawyer has lodged an appeal which is scheduled to be heard on 18 July. Rajab still faces three further court cases.

In November 2011, a report by the Bahrain Independent Commission of Inquiry (BICI), set up by the king, Shaikh Hamad bin ‘Issa Al Khalifa, concluded that the authorities had committed gross human rights violations with impunity, including excessive use of force against protesters, widespread torture and other ill-treatment of protesters, unfair trials and unlawful killings.

The report urged the government to establish an independent body to oversee the implementation of the BICI’s recommendations; to usher in legislative reforms to ensure laws are in line with international human rights standards; to bring to account those responsible for abuses; to release all prisoners of conscience and to conduct investigations into allegations of torture.

So far the government has done very little. Reforms have been piecemeal and have failed to provide real accountability and justice for the victims.

Violations continue to be committed against those who oppose the Al Khalifa family’s rule. Several demonstrations in June were reportedly suppressed by excessive force.

On 27 June, another activist, Zainab al-Khawaja was hit on her thigh by a tear gas canister shot at very close range while she was documenting incidents during a demonstration in Buri village, south-west of Manama calling for greater respect for the right to peaceful protest. She told Amnesty International the injury left her with a fractured bone and 17 stitches.

Fellow activist Said Yousif Almuhafdah, who works for the Bahrain Centre for Human Rights and who was also present during the attack, filed a complaint in a police station and was told an investigation into the incident would be launched.

Meanwhile, the government is refusing to release scores of prisoners who are incarcerated simply because they called for meaningful political reforms, and is also failing to address the Shi’a majority’s deep sense of discrimination and political marginalization.

Last month, during an official visit to the UK, Bahrain’s Minister of Interior Lt-General Shaikh Rashid bin Abdullah Al Khalifa, insisted that there were no detainees held in Bahrain on account of their opinions but only people “who had committed acts punishable under the law”.

The Bahraini Penal Code contains vaguely worded provisions that can be used to criminalize the legitimate exercise of freedom of expression, association and assembly.

Rajab is facing trial on charges of taking part in an “illegal gathering” and “disturbing public order’ during an anti-government protest in Manama on 6 February. The next hearing for this case is scheduled for 26 September 2012.

Another ongoing trial relates to charges of “illegal gathering” brought against him on 6 June. The next session of this hearing is due to take place on 16 July.

Rajab is also appealing against his 28 June conviction of “insulting a national institution” (the Ministry of Interior) in his tweets. The appeal is due to be heard on 27 November.