The woman who claimed Opposition Leader Bill Shorten raped her in the 1980s - allegations he was cleared over - has slammed police for their investigation.

The lengthy investigation concluded in August of this year, with police electing not to press charges against the Labor leader over the alleged incident at a summer camp in 1986.

The woman, identified only by her first name Kathy, told News Corp she believed the case would have been different if Shorten was not a public figure.

She claimed she provided contact and background details for a key witness, only for police to tell her the supporter could not be found.

"I don’t think I had a hope in hell with the police because of who he is," Kathy, now 44, said.

"If Bill was just a regular guy I think it would have been different.

"The police would have had a load of evidence to do something."

Kathy said she was let down by the handling of her case.

“I have got rights, and they are trying to take away my rights. People are treating me like a nutcase.

“It doesn’t mean I’m stupid or I’m fabricating things.”

Rumours that a senior Labor figure was being investigated over historic sexual assault claims had circled over the preceding months before Mr Shorten's identity was revealed.

On August 21, Mr Shorten confirmed it was he who had been interviewed and cleared over the allegations, describing them as “untrue and abhorrent”.

Mr Shorten addressed the police investigation on August 21, denying the claims. (9NEWS)

“There is absolutely no basis for the claim,” he said in a statement.

“I fully co-operated to clear my name, and that is what I have done.

“The police have now concluded the investigation.

“The decision speaks for itself.