A terse Bill Shorten has brushed aside further questions about his involvement in a damaging rape allegation dating back to the 1980s, pointing out Victorian police have told him there was no case and no charges to be laid.

Mr Shorten revealed on Thursday he was the "senior Labor figure" being investigated by police and that after a 10 month investigation, "there is absolutely no basis to the claims".

Addressing the media on Friday, Mr Shorten said "Yesterday I said in my statement all that I intend to say on this matter. I meant that, I don't to intend to comment any further".

"In all fairness the police have concluded their work, they have made their decision and now I think it's appropriate to draw a line under the matter and that's what I'm going to do."

Mr Shorten faced numerous questions on the matter, but declined to speculate on whether the unnamed woman would come forward to tell her side of the story, whether Prime Minister Tony Abbott should counsel his MPs against bringing it up in parliamentary debate and whether he thought there was a difference between his assertion that he had been cleared and the police statement.

The Victoria Police statement confirmed the investigation had ended and stated "investigating police sought advice from the Office of Public Prosecutions, which advised there was no reasonable prospect of conviction. All parties have been notified that Victoria Police will not be proceeding with criminal charges".

Senior colleagues of Mr Shorten rallied around him on Friday, with friend and factional ally Senator Stephen Conroy acknowledging the matter could be politically damaging to the Opposition Leader.

"I think the important thing … is that the police have gone through an exhaustive examination. They've dealt with all the facts, they've been speaking to all the relevant parties and they've … found there's no case to answer," he told Fairfax Radio station 3AW.

"Is it damaging in the sense that is it welcome for any allegation of this serious nature – and this is a very serious allegation that needed to be treated very seriously. I think that's always a challenging situation. I've watched Bill since the day that he was informed of it perform admirably in extraordinarily challenging circumstances."

Senator Conroy said the Coalition had been "very, very reasonable in not outing Bill's name".

Privately, Labor MPs praised Mr Shorten's handling of the matter but admitted that much would depend on whether the woman chose to come forward and tell her side of the story, or if she pursued civil action.

"It depends on if the individual comes forward," said one MP, who asked not to be named. "People may mutter about it around the traps but they are the sort of people who probably wouldn't vote for him anyway."

Labor Treasury spokesman Chris Bowen said Mr Shorten's decision to name himself showed considerable courage and "I think was the right call for him to make".

Senior Liberal frontbencher Malcolm Turnbull has supported the Opposition Leader for his decision to publicly confront the "very, very painful" rape allegations from nearly 30 years ago.

Mr Turnbull said Mr Shorten did the right thing in raising the damaging allegations.

"I think Bill Shorten made the right decision," the communications minister told the Nine Network on Friday.

"It would be very, very painful to feel you are the subject of an unjust accusation."

Prime Minister Tony Abbott, meanwhile, said that as the matter had been dealt with by police and "I don't think there's really anything more to say about it".

"It's a personal matter and I certainly wouldn't normally be commenting on personal matters, so it seems that it is at an end."

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