The Bahraini government on Monday acknowledged “instances of excessive force and mistreatment of detainees” during this year’s crackdown on political protests, in advance of an independent inquiry to be released Wednesday.

“Twenty prosecutions against the officers involved have been initiated,” according to a statement issued by the government information office in Manama. “This is in no way the limit of the steps that will be taken,” it said. The statement also announced new laws criminalizing torture and establishing an independent human rights institution.

Protests by Bahrain’s Shiite majority against the Sunni royal family began in February, during the earliest days of the Arab Spring protests that continue to roil the Middle East. At least 30 people were killed, hundreds wounded and at least 1,000 imprisoned during and after the initial pro-democracy demonstrations, and the government invited troops from Saudi Arabia and other Persian Gulf countries to assist its security forces.

Attempts to negotiate a resolution failed, and violent clashes have repeatedly erupted. In the summer, King Hamad bin Isa al-Khalifa asked M. Cherif Bassiouni, an Egyptian-American jurist and human rights expert, to lead an independent investigation of the protests, the crackdown and the aftermath.

The government has arranged a public event in which Bassiouni will hand over his conclusions and recommendations to the king and both men will give speeches. In Washington, the Bahraini Embassy has invited the media and dignitaries to a 7 a.m. viewing of the event on live video.

Unlike revolts in Tunisia, Egypt, Yemen, Libya and Syria, the Bahraini opposition has not demanded the wholesale departure of the kingdom’s rulers. Instead, a group of five opposition parties, including the main Shiite party al-Wefaq and the secular Waad party, have called for a transition to a constitutional monarchy.

In a statement last month, the opposition group said the ruling Khalifa family should “govern without powers.” Pro-government media described the document as a power grab by the Shiites, the Reuters news agency reported. The government, with backing from Saudi Arabia, has charged that Iran’s Shiite government is behind the protests.

The contents of the upcoming report and reaction to it by the royal family and the opposition will be carefully watched in Washington. The Obama administration has been accused of using a double standard in calling for the departure of some oppressive Middle East rulers, such as Syrian President Bashar al-Assad, while adopting a more measured tone toward repression in Bahrain, a U.S. ally that hosts the Navy’s 5th Fleet.

Secretary of State Hillary Rodham Clinton defended the approach this month, saying that “situations vary dramatically from country to country. It would be foolish to take a one-size-fits-all approach and barrel forward regardless of circumstances on the ground.”

The administration, Clinton said, had to be able to “walk and chew gum at the same time.”

The Bassiouni report, originally due for completion last month, was postponed after the administration said it would delay final approval of a $53 million arms sale to Bahrain until its release.

In its Monday statement, the Bahraini government said that its “police forces have generally shown admirable restraint when faced with great provocation. Every civilian casualty is a defeat for the government. The extremists know this, and have engaged in reckless provocation.” It said that more than 800 police officers have been injured and four have died during the upheaval.