A former NSW police officer blackmailed four victims into having sexual intercourse as part of an elaborate deception involving social media, a court has heard.

Vaughan Mark Hildebrand faced a NSW District Court sentence hearing today after admitting to 44 offences involving 15 victims over a decade.

Crown prosecutor John Bowers said Hildebrand initially used social media to demand his victims supply him with explicit images - with some of them complying.

Former NSW policeman Vaughan Hildebrand has faced court accused of blackmailing women into sexual intercourse and sending him explicit images of themselves. (Supplied)

Vaughan allegedly demanded the images from some of his victims, threatening to share them with friends, family, partners or colleagues if they then didn't meet his other requests. (Supplied)

The now 30-year-old had a "modus operandi" where he threatened to share images with friends, family, partners or colleagues if victims didn't meet other demands.

Four of the women were blackmailed into having sexual intercourse, the prosecutor said.

Mr Bowers said Hildebrand concealed his identity online and, in some instances, there were "very high levels of deception".

Prosecutors in court said Hildebrand's actions showed 'elaborate planning and deception... motivated by a need for sexual gratification'. (Supplied)

His offending continued after be became a police officer in 2011.

"This is a case, the Crown says, of elaborate planning and deception by the offender in relation to all of his victims, motivated by a need for sexual gratification," the prosecutor said.

Hildebrand will be sentenced at a later date.