Ryan Coleman-Farrow, 30, who worked for Scotland Yard's specialist Sapphire sex crimes unit, is facing 13 charges related to investigations he worked on between January 2007 and September 2010.
The former detective constable allegedly falsely told victims their cases had been dropped and falsified paperwork.
He was suspended shortly before a prostitute, who had accused him of failing to investigate her complaints properly, committed suicide alongside another sex worker.
Jaime Perlman, 26, and Chemaine Chevlene, 31, died after inhaling toxic fumes inside a flat in Putney, South West London in 2010 as part of a suicide pact.
Miss Perlman had left a note inside the flat complaining about the conduct of DC Coleman-Farrow, who had been assigned to her case when she complained that she was being stalked by a former client.
At the time he was already under investigation over his conduct on a string of other cases.
His case was referred to the Independent Police Complaints Commission (IPCC) and Mr Coleman-Farrow was later dismissed from the Metropolitan Police Service.
The IPCC have now announced that he is to be charged with 13 counts of misconduct in a public office.
Rosemary Fernandes, a specialist lawyer with the Crown Prosecution Service (CPS), said the charges related to a period between January 2007 and September 2010.
She added: "The 13 charges include allegations that Mr Coleman Farrow failed to perform his duty in investigating rape and sexual assault cases, falsified entries on the police's Crime Report Information System and falsified records of CPS decisions which had never actually been referred to the CPS."
He is due to appear before Westminster Magistrates Court on June 20.
