The Court of Appeal has set a starting point of 16 years for the very worst rape cases.
The new sentencing guidelines, released on Wednesday, double the previous starting point used by the courts in considering sentences for rape.
The decision establishes four sentencing bands for rape cases, with the lowest being six to eight years jail for offending where aggravating features are either not present, or present to a
limited extent.
The Court of Appeal has also issued guidelines for sentencing in cases of unlawful sexual connection.
The man whose case was the basis for Wednesday's decision has lost his appeal against his sentence.
The convenor of the Law Society's Criminal Law Committee, Jonathan Krebs, says as well as giving guidance to lower courts, the new guidelines also help criminal lawyers to know what their clients might expect.
He says the guidelines will direct the judge to a particular band and he believes that is appropriate.
But leading criminal lawyer Barry Hart believes the new guidelines could result in more people defending charges.
He says setting sentencing bands for drug cases have led to prosecutors and defence lawyers debating which band a case fits into, and the same will occur for rape cases.
Mr Hart says the new bands could also lead to offenders committing worse crimes, because they think they may as well be hung for a sheep as a lamb.
