Victims of violent crime face an "unacceptable ordeal in the courtroom", a former chief prosecutor has claimed.
Unveiling a raft of ideas which could form part of a new victims' law, Mr Starmer said vulnerable witnesses could be questioned by a trial judge, rather than cross-examined by a barrister.
He is part of a Labour taskforce making proposals for England and Wales.
The Conservatives said the government was already piloting new ideas to protect victims.
Victims 'deterred' Ahead of the first meeting of the taskforce, Sir Keir - who served as director of public prosecutions between 2008 and 2013 - said measures previously deemed "no-go areas" should be considered.
"The consensus pretty much is that most victims don't have the confidence to come forward and if they do come forward they say they'd never do it again," he told BBC Radio 4's Today programme.
'A complete shambles'Mary says she was a teenager when she reported an allegation of sexual abuse.
"I had to go to the station and be interviewed by a lone male police officer," she said.
"I heard nothing more until I got a letter telling me the trial date. I was not briefed, I did not meet the legal team. I knew nothing of what to expect.
"I was put on video link. I did not want to be on video link, I wanted to be in the room.
"I was asked probing questions, accused of being a prostitute, promiscuous, a drug taker.
"Victim Support called me and I had one or two meetings with an elderly lady.
"I felt like taking justice into my own hands. I wanted to break into his house and hurt him. No justice was being carried out by relevant authorities. A complete shambles - I have no faith in the system.
"I left feeling that sex offenders are in fact protected by the legal system. They are the ones who are prepped, conditioned and kept informed about the trial."
"Now that isn't good enough."
Labour's taskforce is examining whether victims of violence or sexual abuse should be required to go to a police station to report a crime.
Sir Keir, who stood down as director of public prosecutions last year, said this requirement "puts many off from the start" and suggested this process could take place somewhere else.
He said the combative atmosphere of court cross-examination had obvious downsides for some witnesses, adding: "Perhaps judges should be given the task of questioning young and vulnerable witnesses?"
Making it compulsory for people working with children to report suspicions of sexual abuse could also feature in the victims' law.
The taskforce also includes Labour peer Baroness Lawrence, mother of murdered teenager Stephen, and Peter Neyroud, former chief constable of Thames Valley Police and now a criminologist at Cambridge University.
Labour leader Ed Miliband said: "It is time for a radical change in approach and I am delighted that the taskforce will look at the end-to-end service victims receive."
On behalf of the government, Justice Secretary Chris Grayling said more money than ever before was available for victims' services.
He said: "We are also piloting pre-trial cross-examination to help young and vulnerable witnesses give evidence without going through what can be an aggressive and intimidating court experience."
A new victims' panel would allow people affected by crime to tell ministers about their experience, he said.
He added: "We will continue to work with others to ensure victims get the help they need to come to terms with and recover from the traumatic effects of crime."
In Northern Ireland, a spokesman for the Department of Justice said it would soon be setting out plans for a "victim charter", while in Scotland a Victims and Witnesses Act came into force earlier this year.