The report on torture at Abu Ghraib prison is apparently still classified. But it is now widely available on the internet, including here:
http://www.globalsecurity.org/intell/library/reports/2004/800-mp-bde.htm
TORTURE REPORT MAY HAVE BROKEN CLASSIFICATION RULES
By classifying an explosive report on the torture of Iraqi prisoners as "Secret," the Pentagon may have violated official secrecy policies, which prohibit the use of classification to conceal illegal activities.
The report, authored by Maj. Gen. Antonio Taguba, found that "between October and December 2003, at the Abu Ghraib Confinement Facility, numerous incidents of sadistic, blatant, and wanton criminal abuses were inflicted on several detainees."
"The allegations of abuse were substantiated by detailed witness statements and the discovery of extremely graphic photographic evidence," Gen. Taguba wrote.
These specific observations, and the report as a whole, were classified "Secret / No Foreign Dissemination."
Why the secrecy?
"There's clearly nothing in there that's inherently secret, such as intelligence sources and methods or troop movements," an astute reporter noted at a Pentagon press briefing on May 4. "Was this kept secret because it would be embarrassing to the world, particularly the Arab world?"
"I do not know specifically why it was labeled Secret," replied Gen. Peter Pace.
Defense Secretary Donald Rumsfeld said he did not know why it was classified, either. "You'd have to ask the classifier," he said.
http://www.fas.org/sgp/news/2004/05/dod050404.html
But the classification may have been more than simply unnecessary. It might have been a violation of official policy, which forbids the use of secrecy to cover up crimes:
"In no case shall information be classified in order to ... conceal violations of law, inefficiency, or administrative error [or to] prevent embarrassment to a person, organization, or agency...," according to Section 1.7 of Executive Order 12958, as amended by President Bush (EO 13292):
http://www.fas.org/sgp/bush/eoamend.html#1_7
In a lawyerly reading, the Pentagon might respond that the document was not specifically classified "in order" to conceal violations of law, even though that was the direct consequence, but for some other purpose.
The fact remains that classification served to conceal illegal activity for months, if not longer.
Furthermore, there is no effective mechanism to enforce even the executive branch's own standards and policies on classification. Rather, the Abu Ghraib torture scandal came to light through an unauthorized disclosure of classified information, for which one must be sadly grateful.