An American report published today, Tuesday, revealed an aspect of the excesses of the security forces and American prosecutors during the investigations with the detainees led by the concealment of evidence of innocence and false testimony, considering that they are no less dangerous than the police violations that have sparked and still are a wave of widespread protests.

The authors of the report - which bears the title of the "National Registry of Acquittal Decisions" - examined the files of about 2,500 people who were acquitted after wrongly convictions over the past 30 years.

The report - a joint project between the University of Irvine in California and the University of Michigan - stated that illegal or unethical behavior by police officers as well as by prosecutors contributed to more than half of these judicial errors.

According to the report, "the most frequent mistake is concealing evidence of innocence, which was the cause of 61% of wrongful convictions for murder, exerting pressure on witnesses, false testimonies during trials, and drug use of suspects."

The authors of the report also pointed to "the excessive use of force that was condemned during the massive protests," explaining that "African Americans are more victims of such violations than white suspects, especially in murder or drug cases."

Regarding mistakes during arrests, the authors of the report stated that only 17% of judicial errors were followed by penalties, but these errors have major consequences for the victims. People who were wrongly convicted of murder spent an average of 13.9 years in prison before being acquitted.

The report pointed out that among them is Michael Morton, who spent about 25 years in prison in Texas on charges of killing his wife, before his innocence was finally proven.

"The public prosecutor did not present during the trial neither the testimony of their 3-year-old son who acquitted his father, nor the testimony of the neighbors who spotted a suspicious man in front of their home," the report stated.

In 2011, DNA analyzes revealed the real perpetrator after he had killed another woman in the meantime.

Researchers believe that police officers and prosecutors "are under pressure in murder cases to find the perpetrators, and if the case cannot be resolved quickly, the authorities may tend to resolve it, especially if they are convinced that they are holding the perpetrator."

In the context of talking about police reform, the authors of the report suggested compulsory recording of all interrogation sessions, or clarifying procedures for preserving physical evidence. They also emphasized the need to change the "culture" that drives police officers and prosecutors to "error."