Human rights groups have welcomed the acquittal in Kuwait of five opposition activists accused of insulting the ruling emir on their Twitter accounts.
The ruling could become "a victory for free speech," the international group Human Rights Watch said.
Since last October Kuwait's public prosecutor has charged at least 35 people with insulting the emir.
Opposition leaders say the charge is being used to silence political dissent in the Gulf nation.
Last December the opposition boycotted parliamentary elections in protest against a new electoral system which it said favoured pro-government candidates.
Turn-out in the vote was low and since then there have been regular demonstrations.
The five online activists - Muhammad al-Ajmi, Faris al-Balhan, Abdul-Aziz al Mutairi, Fahd al-Jufaira and Rashid al-Enzi - were acquitted of insulting the Emir via Twitter on Wednesday.
But other activists - including three former opposition MPs - have been convicted on the same charges, and one of the acquitted Tweeters - Mr al-Enzi - was sentenced to two years in jail last month in a different case.
"Kuwaiti authorities should take a cue from this decision and revoke sentences and drop charges against others accused of offending the emir," Sarah Leah Whitson of Human Rights Watch said.
Although Kuwait allows more freedom of speech than some Gulf states, insulting the emir or criticising him in public is a crime against state security punishable by up to five years in jail.
The opposition say the ruling al-Sabah family should move more quickly towards a constitutional monarchy with greater democratic accountability, where Kuwait's oil wealth is shared more widely.