Officials at the Criminal Injury Compensation Authority told women their drinking was a 'contributing factor' in their ordeal.
The standard taxpayer-funded payouts of £11,000 were cut by as much as a quarter.
The rules of the CICA scheme allow payments to be reduced in cases where victims are partly to blame - such as by provoking an attacker.
But revelations that the rules have been applied to at least 14 rape victims in the past year alone drew furious protests yesterday, with lawyers branding the approach 'appalling'.
The issue came to light after one rape victim, referred to only as Helen, received a letter from the CICA saying her compensation was being cut from £11,000 to £8,250.
It said: 'The evidence that we have shows that your excessive consumption of alcohol was a contributing factor in the incident'.
She said the letter 'felt like a slap in the face', adding: 'It felt like I was being punished for having the audacity to step up and say "I don't think this should have happened to me". It was like going back to the 1970s, saying "she was asking for it".
'How else could you read the letter but as saying it's my fault I was raped?'
Helen was raped four years ago, when she was 25, after a night out in London's West End during which she believes her drink was spiked.
She told the Guardian the cut in compensation 'was just so cruel and unthinking and so wrong because there is nothing you can do to prevent yourself being raped.
The good news is that the authority has agreed to stamp out the practice, insisting the cases identified so far had been isolated errors. The bad news is that someone with enough power in the CICA to reduce benefits still holds the notion that women are somehow to blame when they are attacked. "Helen" says it best when she says:
Update 8/24 - Take Action. Sign the petition to tell the CICA: Take responsibility for your initial mistake and restore benefits in all 14 cases!
'It is not illegal to go out and have a drink, it is illegal to rape somebody.'