On Friday evening, Devonte Brown was charged with conspiracy to commit murder, over the shooting of Sasha Johnson, Black Lives Matter activist, in May.
Mr Brown, 18, is the second teenager to be charged with conspiracy to commit murder over the incident.
On 26 May, five others were arrested in connection with the shooting. Four have been released on bail until late June.
The fifth, Cameron Deriggs, 18, however, was charged with conspiracy to commit murder at Westminster Magistrates’ Court on 29 May. He too was remanded in custody, and will appear at the Old Bailey on 25 June.
Ms Johnson, mother of two and a member of the Taking The Initiative Party, was shot in the head at a house party in Peckham, south London, on Sunday 23 May. She had been in the back garden of the house, when a group of men burst into the party and opened fire. She remains in hospital in critical condition.
Detectives are actively seeking more information on the shooting and are asking anyone with information to come forward by calling the police on 101 and quoting reference 1172/23MAY or reporting anonymously through Crimestoppers on 0800 555 111.