Ahmed Mansoor, Nasser bin Ghaith, Fahad Salim Dalk, Ahmed Abdul Khaleq and Hassan Ali al-Khamis stand accused of "publicly insulting" top officials in the UAE after being arrested in April.On Sunday, four international human rights groups - Amnesty International, the Arabic Network or Human Rights Information (ANHRI), Front Line Defenders, and Human Rights Watch (HRW) - released a statement condemning the trial of the five activists and called for their release.
"UAE authorities should drop charges against five activists arrested after they called for democratic reforms," the statement read.
Ahmed Mansoor, an engineer and human rights advocate, and Nasser bin Ghaith, an economist and lecturer at Sorbonne University in the UAE, are being charged with using the site, UAE Hewar (Dialogue) to "conspire against the safety and security of the state in association with foreign powers," according to rights groups.
Mansoor also faces charges for inciting others and calling for demonstrations. In March, he supported a petition signed by more than 130 people demanding an elected parliament with legislative powers.
Gamal Eid, director of ANHRI, said it was not only the five bloggers being targeted by the arrests. "They arrested the five to send a message to other online activists that it's not allowed to talk about democracy [in the UAE]," Eid said.
"We feel it's a step back for freedom of speech in the UAE because it's an accusation against bloggers and activists ... because of what they wrote on [an online] forum about democracy. It's not a crime to talk about reform and democracy," Eid told Al Jazeera.
The arrests of the five men is one of the first incidents in recent years when people have been tried for things they've written or said, and that has rights groups worried.
"It shows a dramatic increase of repression by the Emirati government and intolerance for any dissent," said Samer Muscati, a researcher at HRW focusing on the UAE, speaking to Al Jazeera.
In 2007, two reporters on the UAE's English-language Khaleej Times newspaper were sentenced to prison for "libel". Sheikh Mohamed bin Rashid al-Maktoum, prime minister of the UAE and ruler of Dubai emirate, issued a decree that journalists shouldn't be jailed for their work.
However, since the wave of uprisings in the Arab world began in late 2010, some Arab leaders have sought to pre-emptively block any forms of dissent by targeting activists and dissidents.
Muscati said that the uprisings had made "these authoritarian governments realise that their grip on power isn't as strong as they think."
After the Jurists Association and the Teachers Association supported calls for reform in April, their elected boards were both disbanded and replaced by people appointed by the state.
Rights groups have reported threats against some of the defendants and condemned the "intimidating online and satellite television campaign" that has tried to paint the men as religious extremists and foreign agents.
A Facebook page denouncing "Ahmed Mansour and his gang" has nearly 30,000 supporters.
The government blocks a number of websites that discuss politics and government, like Hewar, Muscati said. "That's the irony; that other sites that viciously attack the activists are allowed to continue."