The U.S. Supreme Court orders thousands of prisoners released in California (Brown v. Plata) [PHOTOS]

Supreme Court demanded California's prison system to reduce its inmate population over two years in one of the country's biggest prisoner release order. 

The Supreme Court case is Brown v. Plata, No. 09-1233.

Thirty three adult prisons in California were designed to keep around 80,000 inmates and now hold about 145,000.

This prisoner release is mainly due to the medical and mental health care had fallen below the Constitution's  standard, Justice Anthony Kennedy said. More than 700 prisoners are waiting to see a doctor for care and up to 54 inmates are sharing one single toilet.

California  had been ordered to cut the prison population by 46,000 inmates to be a reasonable  level in 2009.

Improving California prisons' conditions in has turned into a major legal, political and financial issue due to the worsening budget crisis in California.

However, dissenters fear the increase of crim.

"I fear that today's decision, like prior prisoner release orders, will lead to a grim roster of victims," said Samuel Alito, one of the dissenting justices.

Meanwhile, California had argued that forcing it to release inmates would increase murders and crime.

The tough sentencing laws adopted during the 1990s was said to fuel the dramatic rise prison population in California.

More than 2 million people were imprisoned in state and local prisons in the United States.

Prisoners place their hands on a wall as they are brought to jail by Orange County sheriff's deputies in Fullerton, June 23, 2009.

Prisoners at the Richard J. Donovan Correctional Facility in San Diego housed in a gymnasium due to overcrowding, September 14, 2009.

A cell in the Secure Housing Unit of Pelican Bay State Prison in Crescent City, April 27, 2005. Such cells are typically used to house violent inmates who are allowed to leave the cell only for 90 minutes of solo exercise a day.

An inmate sits at the Orange County jail in Santa Ana, May 24, 2011.

An inmate at the Mule Creek State Prison in Ione, February 13, 2007.

An inmate in his cell at the California Medical Facility (CMF) in Vacaville, March 17, 2010.

A man looks at a wall with photos of the most dangerous death row inmates in the facility, inside the Adjustment Center at San Quentin, October 25, 2004.

A guard at San Quentin prison checking the doors of cells housing death row inmates, October 25, 2004.

An inmate is checked into the Orange County jail in Santa Ana, May 24, 2011.

Prisoners congregate at the Mule Creek State Prison in Ione, February 13, 2007.