In 2023, a young and ambitious Liberal moderate was on the brink of securing one of the most powerful roles in the party: state director of the New South Wales branch. Three years later, he is playing a key role in selecting and vetting One Nation candidates determined to beat his former colleagues.

Multiple Liberal sources familiar with recruitment for the position, which involves running election campaigns and managing fundraising, confirm Mark Jones was among the final three candidates for the role before his career advancement was ultimately blocked.

Internal One Nation documents seen by Guardian Australia show Jones – who quit the Liberal party in January – has become integral to One Nation’s state election campaigns performing similar administrative functions.

Since joining One Nation as a political consultant in February, Jones has helped redesign the party’s candidate selection and vetting process and sat in on interviews.…