The man who murdered British backpacker Grace Millane has had a further bid to appeal against his conviction rejected by New Zealand's highest court.

Jesse Shane Kempson murdered Millane on the weekend of her 22nd birthday in December 2018.

He admitted his actions - during what he said was consensual rough sex - caused her death.

But he denied a charge of murder.

A jury found him guilty after a high-profile trial in the High Court at Auckland and he was jailed for life.

Following a failed appeal in the Court of Appeal, Kempson then applied to the Supreme Court for leave to mount a fresh appeal against his murder conviction.

A decision was released today revealing Kempson's application had been dismissed entirely.

"In their verdict, the jury showed that they were sure that if the applicant did not intend to
kill the deceased, he at least intended to inflict bodily injury which he knew was likely
to result in death," today's ruling said.

"The most that could be taken from the applicant's account is that Ms Millane may have consented to the application of manual pressure to her neck for the purposes of sexual gratification.

"There is nothing in what the applicant told the police to suggest that she consented - or he believed she consented - to the infliction of bodily injury of a kind likely to kill her.

"For these reasons, albeit slightly differently expressed, the Court of Appeal was of the view the argument failed "as a matter of fact".

"We see no apparent error in this conclusion."

The court further explained its dismissal.

"The conclusion of both Courts is that consent does not, at least in the circumstances of this case, provide a defence to the intentional infliction of bodily injury known to be likely to result in death," the decision said.

"There is insufficient doubt as to that conclusion to warrant leave being granted.

"This is because it is difficult to see how a court could responsibly hold that consent is a defence to violence carried out with murderous intent."

It was also revealed Kempson faced two other trials this year for sexual violence against two women after the high-profile murder.

He was found guilty of all nine total charges at both trials, including rape, which he is now appealing against.

SEXUAL HARM - DO YOU NEED HELP?

If it's an emergency and you feel that you or someone else is at risk, call 111.​

If you've ever experienced sexual assault or abuse and need to talk to someone contact the Safe to Talk confidential crisis helpline on:

• Text 4334 and they will respond
• Email [email protected]
• Visit https://safetotalk.nz/contact-us/ for an online chat

Alternatively contact your local police station - click here for a list.

If you have been abused, remember it's not your fault.