It is also reviewing the way it chooses and vets contestants amid fierce criticism from one of the show's key sponsors. The Herald can now reveal 22-year-old Auckland marketing assistant Danielle Robinson, known as Dani, has a drink-driving conviction.
She is considered a frontrunner on the show after she went jet-skiing with the Bachelor - 26-year-old Auckland businessman Arthur Green - on last night's episode and was one of two contestants to get a rose before the formal ceremony on Tuesday's premiere.
On Saturday the Weekend Herald revealed Danielle Le Gallais, 33, was jailed for 18 months for stealing nearly $40,000 from her employer in 2005. She was also charged over returning goods to The Warehouse not bought there in exchange for cash, giving police a false name and having an incorrect driver's licence.
The show's makers were unaware of her criminal past.
Bachelor Green yesterday said he was "very surprised" to learn of Le Gallais' murky past.
"It didn't affect my judgment of her that much I suppose, because I'd gotten to know her before all that news came out."
Show sponsor Lindauer said yesterday it had been "let down" by MediaWorks.
"Lindauer does not condone drink driving, irresponsible or illegal behaviours.
"We are extremely disappointed with MediaWorks and their production company as we explicitly requested that full background checks be carried out on all contestants as part of our conditions ..."
Production company EyeWorks was tasked with doing checks on the 21 women vying for Green's attention.
Lindauer's spokeswoman said the brand was reviewing all activities as programme partner and ensuring its name was not associated with any individual contestants.
MediaWorks said that while Le Gallais did not declare her conviction, Robinson had acted correctly in declaring her conviction and the crime was not seen as affecting her place on the show.
On Monday the company dumped X Factor judges Natalia Kills and Willy Moon for bullying a contestant.
The show was also criticised for downplaying the role of a contestant in a manslaughter case.