A scheme providing compensation to victims of crime unfairly discriminates against some of the most vulnerable people, a campaign group has argued.
Some victims of violent crime can get compensation
Victim Support said children "groomed" and sexually abused were not entitled to the government payments.
And it said people on benefits often had them stopped or reduced after receiving compensation for a crime.
The government defended itself against claims the scheme was "unethical" and said it was the world's most generous.
Victim Support said the Criminal Injuries Compensation Scheme (CICS) must be reassessed to end what it called "unethical and frankly indefensible anomalies".
It said the scheme will normally only make awards to victims of sexual assault if the attack involved physical violence.
It said this excluded children who agree to sex after being groomed by paedophiles.
The group said the rules were "perpetuating an old-fashioned - and insulting - notion that physical violence is an essential component of a sexual offence".
The report, Insult to Injury, continued: "It has caused extreme distress to a number of victims who, we believe, should be entitled to compensation."
Denying claims the system discriminated against child sex abuse victims, the Home Office said: "Every case is looked at on its own merits, and if there was grooming or abuse of power that took place they might be eligible for compensation."
Other people excluded from compensation payments include those assaulted or abused by someone living as a family member before 1 October 1, 1979.
The government spokesman said it would be impractical for this group to be included and could prove too costly.
Victim Support said it was also "grossly unfair" that
relatives of a murder victim are denied compensation if the dead person had a criminal record.
The charity argued that compensation is paid to ease pain and suffering after a crime and is not to cover the cost of living.
It urged the government to correct the problems in a planned review of the compensation scheme.
The group's chief executive, Dame Helen Reeves, said failing to do so would mean "those who have already suffered from acts of violence will continue to be subject to discrimination at the hands of the very system that it meant to demonstrate society's concern for them".
The Home Office added: "No amount of money can make up for the injuries and trauma of being a victim of crime, but our CIC Scheme is the most generous in the world, receiving nearly £200m in government funding each
Victim Support helps about 20,000 people a year to make claims after they have suffered a crime.
In all 80,000 people a year apply to the scheme, with half receiving payments of between £1,000 and £250,000.