Human Rights Watch on Wednesday called on rights officials meeting in Geneva for a UN review of Jordan's record to press Amman to lift restrictions on freedom of expression.
Country representatives gathering under the United Nations Human Rights Council for the review process on Thursday "should press Jordan to amend its penal code to remove vague charges that limit rights to free expression, assembly and association," HRW said in a statement.
Although Jordan rewrote its constitution in 2011 to guarantee basic freedoms, prosecutors invoke a 1961 penal code to take dozens of protesters before a military court on vague charges, including "lengthening the tongue," used to prosecute insults to or criticism of King Abdullah II, the US-based watchdog said.
"What good is the new constitution if Jordanian prosecutors can keep undermining basic rights by using the old penal code?" asked Joe Stork, deputy Middle East director at HRW.
"Other countries should use this opportunity to press Jordan to update the penal code to protect the rights the new constitution is supposed to guarantee."
The periodic review comes just weeks before Jordan's bid for a three-year seat on the 47-member rotating Human Rights Council, on November 12.
"As a candidate, Jordan should make commitments to end continuing abuses and set timetables to carry out human rights reforms," HRW said.
The rights groups also criticised government measures that limit free expression and media freedom.
In July, Jordan blocked more than 200 news websites for failing to comply with 2012 press law amendments requiring them to register with the government's press department.
The amendments also make the owner, editor and director of an electronic publication responsible, along with the author, for comments or other posts from users on the website.
Also, the editor and publisher of Jafra News website have been in detention since September 17 without bail for posting a YouTube video showing a man, allegedly a Qatari prince, sitting on a bed with a woman.
"More than two years after King Abdullah announced a reform process, Jordan has neglected to improve some key areas," Stork said.
"Jordan should take concrete, visible steps before the council elections to show it's willing to improve human rights, including freeing journalists and peaceful protesters detained on vague, impermissible charges."