One last rape charge against businessman and convicted child sex offender Peter Maxwell Stewart has been dismissed in the High Court at Christchurch and he has been given back his passport.

The charge was count nine when he was on trial on historic sex charges in November and December 2007.

Stewart, now aged 63, was convicted on seven charges, acquitted on four, and the jury was not able to agree on count nine. It was an allegation of the rape of the woman involved in all his offending, in rural Canterbury, in August 1973.

The woman is now in her 40s but she had given evidence in the High Court trial of sexual abuse by Stewart from the time she was aged about eight years, until she was 18.

After the guilty verdicts, trial judge Justice Graham Panckhurst sentenced Stewart to three-and-a-half years' jail for rape, sodomy, and indecent assault, in February 2008.

Last week the Parole Board decided that he could now be released after serving 14 months of his sentence.

He has been reported as a model prisoner during his term at Rolleston Prison near Christchurch, and the board decided he would not pose any undue risk to the victim or the community.

He will have to live at an approved address and not have any unsupervised contact with children aged under 16.

The crown must have considered whether to go ahead with a further trial on the outstanding charge, but at the pre-trial session today, it said in a memorandum that it offered no evidence and Justice Panckhurst discharged Stewart.

Defence counsel Jonathan Eaton was also given an envelope containing Stewart's passport.

Stewart's release was expected to take place today.