Ms Becker has served 12 years in prison for six other murders
Germany has charged a former member of the radical far-left Red Army Faction (RAF) militant group over the 1977 murder of a federal prosecutor.
Verena Becker, 57, was arrested last August for her suspected role in the ambush of Siegfried Buback. Two men escorting him were also shot dead.
Ms Becker is accused of being an accessory to the murder - one of the RAF's most notorious attacks.
The RAF, also called the Baader-Meinhof gang, killed more than 30 people.
DNA evidence implicating Ms Becker was found on a letter in which her group claimed responsibility, police said.
The three victims were shot dead by two people on a motorcycle as their car stopped at traffic lights en route to a Karlsruhe court.
Although Ms Becker was arrested the month after the Buback assassination, after a shoot-out with police, there was insufficient evidence at the time to convict her of his murder.
She was sentenced to life imprisonment for her involvement in six other murders, but was pardoned by then President Richard von Weizsaecker in 1989 and released.
The RAF broke up 10 years ago. It targeted bankers, businessmen, judges and US servicemen. Bodyguards and drivers were also gunned down in the gang's attacks.