Sexual consent laws should be amended in NSW so that a person who has an unreasonable but honest belief in consent is not guilty of a crime, the professional body representing the state's 2400 barristers has told the state government.

The Berejiklian government commissioned a review of sexual consent laws in May following the high-profile acquittal of Luke Lazarus, who was accused of raping an 18-year old woman in an alleyway behind his father's Kings Cross nightclub in 2013.

Luke Lazarus, son of prominent nightclub owner Andrew Lazarus, was acquitted of sexual assault last year. Credit:Facebook

One of the key issues in the case was whether the then 21-year-old Mr Lazarus had "reasonable grounds" for what the NSW District Court found was an honest but mistaken belief his alleged victim, Saxon Mullins, was consenting to anal sex.

Under NSW law, if a person has "no reasonable grounds" for believing there is consent they are deemed to have knowledge of lack of consent – a key element of the offence of sexual assault.