A police officer will be prosecuted for allegedly kicking a 15-year-old boy held in handcuffs at a London police station in the aftermath of last summer's riots.
Pc Joseph Harrington will be charged with assault after the Crown Prosecution Service admitted that an earlier decision not to take action against him was "clearly wrong".
It said a prosecution was necessary to "maintain confidence in the criminal justice system" in the second case of its kind in which the CPS had reversed a decision not to prosecute after allegations against a police officer.
The case involving Pc Harrington came to light just a few hours after one of his colleagues was recorded allegedly using racist slurs while he was arresting a 21-year-old black man, Mauro Demetrio, from east London.
The officer in that case, Alex MacFarlane, is due in court later this month. The CPS again reversed its decision not to charge him after an investigation by the Independent Police Complaints Commission. The two cases prompted a storm of criticism and led to a review of more than a dozen cases within Britain's biggest police force in which officers were accused of racism.
The Commissioner of the Metropolitan Police, Bernard Hogan-Howe, who declared he would not tolerate racism, said all the inquiries being carried out by his force were likely to be completed by the end of this week.
In a statement, Alison Saunders, the chief prosecutor for the CPS in London, said that the decision to charge Pc Harrington followed a review into his case started last month, which found the original decision to be wrong.
"It is clear that the allegation of using excessive force on a handcuffed 15-year-old in custody is a serious matter," she said.
"I have taken the decision in this case that not only is there sufficient evidence to provide for a realistic prospect of conviction, and that a prosecution is required in the public interest, but that a prosecution is necessary in order to maintain confidence in the criminal justice system."