CAMPAIGNERS have voiced concerns after the number of convictions for rape and attempted rape in Scotland dropped by one-third in a year, largely owing to the controversial Cadder legal ruling.

Government statistics released yesterday show there were just 36 rape and attempted rape convictions during 2010/11, compared with 54 in the previous 12 months.

The number of cases being brought to court by prosecutors also fell by 31% from 118 to 81.

The Crown Office and Procurator Fiscal Service (COPFS) said the drop was a result of the Supreme Court Cadder ruling, which prevents police officers interviewing suspects without access to a solicitor.

Government statistics released yesterday show there were just 36 rape and attempted rape convictions during 2010/11, compared with 54 in the previous 12 months.

The number of cases being brought to court by prosecutors also fell by 31% from 118 to 81.

The Crown Office and Procurator Fiscal Service (COPFS) said the drop was a result of the Supreme Court Cadder ruling, which prevents police officers interviewing suspects without access to a solicitor.

Rape Crisis Scotland described the figures as worrying, particularly in light of a 14% increase in the number of rapes and attempted rapes reported to police.

A spokeswoman for the charity said: "It is a matter of great concern to see the number of prosecutions has dropped by 31% compared with the previous year.

"Reporting a rape can take a great deal of courage, and it can be devastating for rape survivors to find their case will not make it to court."

The Cadder judgment, published by the Supreme Court in October last year, ruled it was a breach of the European Convention on Human Rights to allow an accused to be detained and interviewed by police without the right to a solicitor.

A COPFS spokesman said this meant that in many cases dealt with since then "essential evidence" from police interviews had been lost and the Crown was unable to proceed with cases that would previously have gone to court.

He added: "The Supreme Court ruling in the Cadder case has meant that in many cases essential evidence from admissions made by a suspect in police interview has been lost to the Crown.

"Given the nature of the crime of rape and attempted rape, admissions by the suspect were often essential to provide the necessary corroboration, especially of penetration.

"COPFS was therefore unable to proceed with cases that relied upon admissions made by the accused and which could have proceeded prior to the Cadder case."

Acquittals for rape and attempted rape are high, with 38% of the 81 people proceeded against found not guilty in 2010/11, according to the Criminal Proceedings report. The cases also attracted shorter sentences in 2010-11, with average jail terms falling 5% to 2085 days.

The figures sparked calls from opposition politicians for the Scottish Government to do more to ensure convictions.

Scottish Labour's Justice spokeswoman, Johann Lamont, MSP, said: "It is deeply concerning that despite the number of rapes and attempted rapes reported by police increasing last year to a five-year high, the number of offenders convicted for rape has hit a 10-year low and rapists are now getting shorter sentences.

"These statistics should be a serious wake-up call for the SNP Government to redouble its efforts to ensure those guilty of these horrific crimes are brought to justice."

Scottish Liberal Democrat spokeswoman Alison McInnes, MSP, also voiced her concerns over the figures.

She said: "Rape blights the lives of victims and their families, yet these low conviction rates confirm the difficulty in securing justice in many cases.

"Collecting admissible and high-quality evidence that can bring a conviction is clearly a problem and consideration must be given to more specialised support in that area."

A report on the Scottish legal system was commissioned as a result of the Cadder ruling and in his review, Lord Carloway recommended that corroboration be abolished.

The Rape Crisis Scotland spokeswoman said: "These figures make the implementation of Lord Carloway's recommendation to remove the requirement for corroboration even more crucial."

A Scottish Government spokesman said they were giving "very careful consideration" to Lord Carloway's review.

He added that, despite the drop in the number of successful prosecutions, the conviction rate for 2010/11 was similar to previous years at 44%.

The spokesman said: "Last year we brought in the Sexual Offences Act, which brought greater clarity to the prosecution of sexual crimes. This is important legislation that has improved the law.

"In establishing the National Sex Crimes Unit, the Crown Office has established a team of specialist prosecutors to ensure these cases are given the best available consideration and preparation."