Former politician and police prosecutor Graham Capill was today handed a nine-year jail sentence for his sex crimes against three young girls.

The ex-Christian Heritage Party leader, 46, was sentenced in Christchurch District Court for raping a girl under 12, indecent assault and unlawful sexual connection.

Judge Robert Kerr sentenced Capill to seven years in prison for rape, three years for unlawful sexual connection to be served concurrently, and two years for indecent assault.

He set no minimum parole period.

Judge Kerr said he had decided on a nine-year sentence after taking into account the mitigating factor of Capill's guilty pleas, which had saved the three complainants from having to give distressing personal details about the offending.

He also took into account that the offending was over a period of 12 years, from 1990 to 2002, and that the victims had been left distressed, suffered anxiety, loneliness, despair, and that one had considered suicide.

Judge Kerr said there was an element of premeditation over such a long period.

It was revealed yesterday that Capill emailed friends two weeks ago saying that his sex with one of his young victims was consensual.

He asked his friends to pray for a lenient judge and prison term.

Capill raised the possibility of being sent to prison for nine years, and said he hoped to serve only one-third of his sentence.

His rape victim was just eight when he began abusing her, according to the Crown. He raped her twice before her 12th birthday.

Capill was the minister at the Christian college the rape victim attended. What began as groping the then-eight-year-old had escalated to rape by the time the abuse ended years later.

For another girl, being sexually abused by Capill formed her earliest childhood memory.

In February this year, when Capill was working as a police prosecutor in Christchurch, Anglican vicar Wally Behan alerted police to allegations involving a young girl.

In April, Capill admitted indecently assaulting that girl and was awaiting sentence when the other two women came forward, and in June he pleaded guilty to rape, three further charges of indecent assault and unlawful sexual connection.

Defence lawyer Jonathan Eaton said yesterday Capill understood the gravity of his crimes.

"Implicit in his guilty plea (to rape) was acceptance that this was not consensual activity," Mr Eaton said.

Security at the packed Christchurch courthouse was tight today, following an attack on Capill as he was leaving court in March by former boxer Danny McNally.

During the 45-minute sentencing, Capill sat with head bowed and reached for a handkerchief from time to time.

Crown prosecutor Deidre Orchard had asked the judge consider a sentence beginning at between nine and 12 years.

Judge Kerr said he was aware of the difficulty Capill may have serving his sentence given his public profile but said everyone was equal before the law.

The judge said the email sent by Capill to supporters demonstrated he had yet to fully appreciate the enormity of his offending.

He said Capill had used emotional power over his victims.

After his arrest, Capill had told his probation officer of his feelings of lust and excitement as the opportunities arose.

Even though he pleaded guilty when the first charge of indecent assault was made, Capill had also lied to deter other girls from complaining, and there was also a suggestion Capill had used his knowledge of the law as a police prosecutor to avoid the accusation of rape, Judge Kerr said.

Capill had set himself up as the epitome of virtue and moral probity to conceal his ugly behaviour. He had been living a lie, Judge Kerr said.

However, other mitigating factors included Capill having no previous convictions.

Judge Kerr also noted that Capill himself claimed to have been sexually abused as a teenager by a man in authority.

At the conclusion, Mr Eaton handed journalists a media statement from Capill:

I am ashamed and greatly regret my past actions. Most appalling is the fact I've hurt those closest to me. I know many people look to me as a campaigner for moral values. I recognise the utter hypocrisy between what I said in public and did privately. I apologise unreservedly to the people of New Zealand for that. What I said publicly is what I believed and still do. I pray that God will have mercy on me and forgive me. I also pray for healing and God's help and love to surround my family whom I've hurt and let down so badly.