Magdi Abdelhadi BBC Arab affairs analyst

The religious police enforce Islamic codes of dress and morality

Members of the feared religious police in Saudi Arabia are for the first time due to stand trial over the deaths in their custody of two men.

The deaths, which occurred a few weeks ago, sparked a media uproar, leading to calls for a re-evaluation of the force's role and responsibilities.

One of the dead men had been accused of socialising with an unrelated woman, the other of alleged alcohol peddling.

Both died shortly after being detained by the religious police.

Members of the force, known as The Commission for the Promotion of Virtue and Prevention of Vice, roam the streets to make sure that shops are closed during prayer time, and that women observe the strict dress code and that they do not mix with unrelated males.

Balance of power

Over the past few years, criticism of the force has grown louder and the Saudi royal family promised reform.

As a result, the religious police had some of its powers curtailed.

But the deaths of the men in custody have reignited the debate about the wide-ranging powers given to its members.

One Saudi columnist wrote that the religious police enjoyed immunity of any kind of accountability and that they have "have taken on the role of the policeman, judge and jury".

The Saudi government has sought to play down the significance of the incidents.

It is a difficult balancing act for the rulers of Saudi Arabia.

The royal family derives its legitimacy from presenting itself as the upholder of Islamic Sharia.

It would not like to be seen as undermining the power of the religious police, neither can it afford to alienate an angry public.

The trial will be watched closely by supporters of the police as well as their critics.

Its outcome will most likely affect the balance of power between the powerful religious establishment and those who want to see change in the conservative kingdom.