A Christchurch detective who had a sexual relationship with a rape complainant is now being investigated for allegedly accessing her case file

Luke Fazackerley met then-22-year-old, Alex McPhail, while investigating her complaint two years ago.

McPhail says their relationship turned sexual - and claims he sent her images of the policing code of conduct, confirming their contact was a breach.

She says the IPCA has since launched a new probe, alleging Fazackerley viewed her file and interview after being removed from the case.

McPhail says it made her feel sick, and vulnerable to emotional manipulation.