At least 46 people died during protests between February and November 2011, a further 26 have been killed since November 2011.
More than 500 allegations of torture or other ill-treatment were received by the BICI in 2011.
Seventeen policemen have gone on trial. Eight have already been acquitted.
At least 80 children are currently held in adult prisons.
Amnesty International has adopted 20 individuals as prisoners of conscience.
According to the Bahrain Watch, the Bahraini government has recently spent at least US$32 million on public relations firms since February 2011.
The Bahraini authorities must immediately release five men sentenced to a year imprisonment for allegedly insulting the King of Bahrain in messages posted on Twitter, Amnesty International said.
Lawyer Mahdi al-Basri, 25, was arrested following a police raid on his home in Karrana, northern Bahrain.
Mahmood ‘Abdul-Majeed ‘Abdullah Al-Jamri, 34, Hassan ‘Abdali ‘Issa, 33, Mohsen ‘Abdali ‘Issa, 26, and ‘Ammar Makki Mohammad Al-Aali, 36, were detained a day later.
The five were tried in separate cases on charges of insulting the King in messages posted on Twitter.
Mahdi al-Basri was accused of posting twitter messages in June 2012 that were traced to his IP address. He has denied the charges, stating that his personal Twitter account was not the one used to post these messages and that he had no connection to the account that used his IP address.
The men were sentenced to one year imprisonment on 15 May under Article 214 of Bahrain’s Penal Code, which criminalizes “offending the emir of the country [the King], the national flag or emblem”.
“The authorities in Bahrain seem to be using every trick in the book to stop people from expressing their views,” said Hassiba Hadj Sahraoui, Middle East and North Africa Deputy Director at Amnesty International.
“Two years after the uprising in Bahrain, and despite the government claiming to have initiated reforms, the Bahraini authorities are stepping up the repression of those daring to express their views, whether via Twitter or on peaceful marches.”
On 14 April, Bahrain’s cabinet endorsed an amendment to Article 214 of the Penal Code, increasing the penalty for offending King Hamad bin Isa Al Khalifah or the country’s flag and other national symbols.
The amendment, which has been referred to the National Assembly, would make such offences punishable by up to five years in prison in addition to steep fines.
In another move to restrict basic rights,,earlier this month the lower chamber of Bahrain’s Parliament proposed new amendments to the Law on Public meetings, processions and gatherings.
This further restricts the right to peaceful assembly by demanding that organizers pay a warranty of 20,000 dinars (US$53,050) for a licence. The organizers must also notify people in the area where the gathering will take place.
Since the start of the uprising in 2011, Amnesty International has documented scores of human rights abuses against peaceful activists in Bahrain, including arbitrary arrests, unnecessary and excessive use of force and torture, and other ill-treatment.
The Bahrain Independent Commission of Inquiry (BICI), appointed by the Bahraini government in June 2011, was charged with investigating and reporting on human rights violations committed in connection with the 2011 protests.
The commission found the security forces were responsible for excessive use of force and arbitary arrests, but no progress has been seen in taking those responsible for the abuses to justice.