A London police officer based in the Parliamentary and Diplomatic Protection Command was charged with rape on Sunday, the Metropolitan Police said in a statement.
David Carrick, aged 46, was charged by police in Hertfordshire, where he was off-duty at the time.
The charge comes days after Wayne Couzens, an officer in the same command, was sentenced to life imprisonment without parole for the kidnap, rape and murder of Sarah Everard in March in a case that shocked Britain and stirred protests over violence against women.
The Metropolitan Police said it was "sickened, angered and devastated" by Couzens' crimes, and its Commissioner Cressida Dick apologised to Everard's family.
The case triggered calls for major reform over how police officers are vetted and how crimes against women are dealt with.
Speaking about Sunday's rape charge, Dick said: "I am deeply concerned to hear the news today that an officer from the Met's Parliamentary and Diplomatic Protection Command has been arrested and now charged with this serious offence.
"I fully recognise the public will be very concerned too."
She said criminal proceedings must now take their course.
Carrick was arrested on Saturday by Hertfordshire Constabulary and suspended the same day by the Metropolitan Police.
(Reporting by Paul Sandle; Editing by Daniel Wallis)
