As the festive season gets under way, Wellington police are peppering bars and clubs with stringent messaging about sexual consent, using the slogan: “Don’t guess the yes.”

The campaign is designed to educate partygoers about the effects alcohol can have on decision making and consent, and began after police noted an increase in sexual harm reports.

Acting Detective Senior Sergeant Ben Quinn said analysis found young women, aged 18 to 24, in the central city were more likely to be victims of sexual harm, while men aged between 23 to 29 were more likely to be perpetrators.

It is also more likely for those involved not to have known each other very long.

“We need to prevent adult sexual assault offending and victimisation by encouraging people to change their attitude around sexual consent and alcohol consumption,” Quinn said.

Posters featuring fictitious text message conversations will be displayed in the city’s bars and clubs. In one version, one friend advises the other to leave a bunch of “wasted” women alone as that behaviour is “creepy”. The latter then agrees to come home.

On another poster, a woman texts a friend, saying she is being harassed by a man who won’t stop bothering her. The friend responds that she’ll “come meet you now”, and pick up dinner for the two of them as well.

“Those who are drinking are in a more vulnerable position and should not be taken advantage of,” Quinn said. “We need to respect each other and remember that intoxicated person could quite easily be your sister, brother, friend or loved one.

“This initiative sends a clear message that sexual assault and abuse won’t be tolerated.”

According to the Sexual Abuse Prevention Network, one in three New Zealand women has experienced a sexual assault in her life time, with an average 186,000 sexual violence offences committed each year across the country. Half of all perpetrators and half of all victims report consuming alcohol in the lead-up to a sexual assault.

Only 7% of sexual violence offences against adults are reported to police, and an even smaller percentage eventually make it to the courts and result in a conviction.

In this year’s budget the Labour coalition government, led by Jacinda Ardern, allocated $320m over four years to combat family and sexual violence.