The announcement, in which Ms Dowie cites a desire to spend more time with family, comes after she was confirmed as Invercargill candidate for National last year and means a new selection process will be needed.
Ms Dowie, who was first elected to Parliament in 2014, took a hit when it was revealed police were investigating a text message, allegedly sent from her phone, to Mr Ross.
The text message, which included the words, ‘‘You deserve to die’’ was sent after the end of an extra-marital relationship between the two National Party MPs.
Well-informed sources said the affair had caused turmoil in National party circles in Invercargill.
Police eventually decided she had no case to answer.
Ms Dowie said it was a privilege to represent Invercargill in Parliament.
‘‘It was a tough decision to make but it is what’s best for my family and I. This decision has nothing to do with Jami-Lee Ross.
‘‘I am a proud Southlander and will continue to support the region.
In a statement yesterday she said, ‘‘despite being re-selected as the candidate, I have made the decision not to contest the seat.
Her proudest achievements included taking a leading advocacy role in aquaculture policy and development as part of the Southern Regional Development Strategy, leading the conservation portfolio and policy development as National’s spokeswoman for conservation, and chairing the Justice Select Committee’s busy legislative agenda including family violence reforms, in her first term.
‘‘It has been a privilege to help many Southlanders behind the scenes on personal constituency matters that have made a real difference in their lives.’’
However, she said she was most proud of her children Christabel and Hunter, who were 4 and 2 at the time she went to Parliament and now wished to be there to share in their successes.
“While this was a difficult decision to make, I feel this is the right decision for me and my family.
‘‘I will fulfil my responsibilities as Member of Parliament for Invercargill and campaign for the National Party up until Election Day. The new candidate for Invercargill will have my full support. I wish the National team all the very best in the upcoming election.’’
National leader Simon Bridges paid tribute to outgoing MPs Ms Dowie, David Carter and Nicky Wagner.
‘‘David Carter, Nicky Wagner and Sarah Dowie have all been fantastic members of our caucus.
‘‘David was one of the most competent and fair speakers we’ve had at Parliament. Nicky was a hard-working minister who fought for our most vulnerable and Sarah has been a valuable and passionate advocate for conservation in Government and Opposition.’’
Mr Bridges announced a reshuffle of the roles held by the outgoing MPs, Waitaki MP Jacqui Dean taking on conservation.
A National spokesman said the party would ‘‘open the process of selecting a new candidate over the coming weeks’’ to replace Ms Dowie.
