Both Iran and Saudi Arabia maintain fairly poor reputations in the Western world for their approach to human rights. While Iran remains isolated through sanctions and is frequently vilified, the oppression of political dissent by Saudi Arabia is frequently overlooked by both their Western allies and the public.
Not only has Saudi imprisoned up to 30 times more political prisoners, conditions in Saudi jails are also notably worse than in Iran.
The United Nations Special Rapporteur on Torture put the number of political prisoners in Iran at around 850 cases formally logged and recognised as politically motivated incarcerations, while Human Rights Watch believe this number could be higher. While there is no definition in international or Iranian law for "political prisoners", these inmates include human rights defenders, political activists, opposition politicians and journalists.
But Iranian government and judiciary officials generally maintain that there are no "political prisoners" in Iran, according to Faraz Sanei, Iran researcher with HRW.
"Many individuals, HRW and other rights groups consider 'political prisoners' as being prosecuted under vague and overly broad national security laws (including terrorism-related charges) and the government considers them 'national security' prisoners."
One article of the Iranian national security laws criminalises the establishment of groups that allegedly aim to "disrupt national security". Another sets a sentence of up to a year of imprisonment for "in any way advertising against the order of the Islamic Republic of Iran or advertising for the benefit of groups or institutions against the order"; while "gatherings or collusion against the domestic or international security of the nation or commissioning such acts" carries a sentence of up to five years.
As is to be expected under a theocratic regime, many of the offences also relate to perceived "un-Islamic behaviour". According to HRW, laws against "insulting" the "Islamic sanctities" or holy figures of Islam are frequently used to incarcerate prisoners. Sanei points out that "insults" have no legal definition within Iranian law.
Members of ethnic and religious minorities are also being incarcerated.
HRW has issued numerous appeals to Iranian government officials regarding the harassment, ill-treatment and torture of political prisoners including the lack of access to adequate and necessary medical care.
"We've also documented the deaths of a handful of political prisoners," says Sanei. "They were in detention facilities or prisons and apparently died as a result of torture, ill-treatment or neglect."
Sanei narrates a serious incident which took place in Tehran's notorious Evin Prison earlier this month, in which uniformed and plain-clothes prison guards severely beat dozens of prisoners held in Ward 350.
"They claimed it was a routine inspection of their cells. The beatings led to serious injuries and thirty of the prisoners ended up in solitary confinement."
HRW launched an investigation which confirmed the reports, despite official denials from Iran. The imprisonments had clearly been politically motivated; many in Ward 350 were arrested in connection with the anti-government demonstrations that took hold of the country following the disputed 2009 presidential election.
The prisoners who were subjected to the beatings have now gone on hunger strike.
However, in general, conditions in Iranian prisons are considered far better than in Saudi Arabia.
The Saudi government maintains one of "the most draconian" prison systems in the world, according to Nader Entessar, a Professor at the University of South Alabama.
"Of course, no prison system is a country club," observes Entessar, "but compared to the prisons in Saudi Arabia, Iran looks rather benign."
Despite a number of serious and violent incidents, Entessar points out that many prisoners are allowed out to visit their families and some are even allowed access to mobile phones and laptops.
Leaked photographs in 2012 showed overcrowding in Braiman prison in Jeddah, with every inch of a long hallway taken up by prisoners sleeping on thin mats. According to a prisoner incarcerated there "My cell was five metres by six metres and I had 23 cellmates." He also reported prisoners being forced to take turns sleeping, as well as sleeping in toilet stalls.
A Saudi national who was incarcerated in 2009 told The Guardian "I was thrown into a prison room barely large enough to accommodate 100 but some 500 persons had been locked in there, in the extreme desert heat."
The prisoner, who has now been released, was shocked to find a large number of expatriates as well as a nine-year-old Nigerian boy.
In addition to overcrowding, prisoners have documented evidence of beatings and torture, including video evidence which shows a prison guard repeatedly using a short piece of plastic to beat two prisoners on the palms of their outstretched hands and the soles of one prisoner's feet. The clips show both prisoners writhing in pain.
Notably, the UK government, a close ally of Riyadh, ignores much of the evidence.
"Compared to many countries, prison conditions in Saudi Arabia are quite good," the Foreign Office blithely states on their website.
The advice, issued to British prisoners unfortunate enough to find themselves incarcerated in Saudi Arabia, advises that access to medical care and food is good. The guidance does not mention the overcrowding issue, although it does note that complaints to Saudi officials go unanswered.
The numbers of political prisoners per capita in Saudi Arabia are far higher than Iran. With less than half the population, Riyadh is reported to have imprisoned up to 30,000 political prisoners.
The numbers however are disputed. The government maintains a website called Nafethah detailing the number of "political prisoners", claiming there are 2,742 inmates. But activists claim that number is far too low. Unnamed sources in 2011 told the BBC's Newsnight that the real number could be in the tens of thousands.
The numbers are harder to estimate as so many Saudi prisons are secret, many run by state "intelligence" departments.
"In the mid-2000s when there was an insurgency inside Saudi Arabia," says Adam Coogle, a HRW researcher specialising in Saudi Arabia, "the security forces detained approximately 11,000 people suspected of involvement in terrorism, many of whom they kept in arbitrary detention without charge or trial for years."
Sources in Saudi Arabia have suggested many of these prisoners did not commit terrorism-related crimes but were imprisoned for their political beliefs.
In 2008 the authorities set up a new court to try these individuals, Coogle says. Last July, he met with a Saudi human rights official who told him the number of political prisoners was around 2,500 – which roughly correlates with official estimates made on the Nafethah website.
Like Iran, peaceful political dissidents and human rights activists are typically convicted under vague charges such as "breaking allegiance with the ruler", "harming public order", "sowing discord", "harming the reputation of the Kingdom", or other ambiguous charges.
Recent cases include Fadhil Al-Manasif, who was sentenced earlier this month to 15 years in prison, a subsequent 15 year travel ban and a 100,000 Saudi riyal fine because of his political activism. Another human rights activist, Waleed Abu Al-Khair, was jailed two weeks ago, he is currently on trial. Typical sentences for "political prisoners" in Saudi Arabia range from several months to over 10 years in jail.
International perceptions of Iran's approach to political freedom are negative. Some 61 per cent of 39 countries surveyed by Pew Research Centre last year believed Iran did not respect their citizens' freedoms. Unfortunately, polling data for Saudi Arabia is not so widely available.
Riyadh rarely receives the same level of criticism from its international partners which include the UK, the European Union and the United States. Without this level of heightened scrutiny, the tens of thousands of political prisoners in Saudi Arabian prisons risk being forgotten about.
Note: This article was updated at 9.56 GMT+1 on May 3, 2014 to correct some factual errors. The number of political prisoners in Iran was quoted by the UN as 850, not Human Rights Watch, who believe the number could be higher. Further, in Sanei's narration of the raid in Tehran's Evin Prison, the number of prisoners who ended up with serious injuries was 30, not all the prisoners.
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