Prime Minister John Key is still refusing to say publicly why he lost confidence in Richard Worth, despite a criminal complaint against the former MP being withdrawn.
Dr Worth resigned from his portfolios, including Internal Affairs, in June.
Mr Key made it clear Dr Worth he had not done so, he would have been sacked.
In answer to renewed media questions on Monday, Mr Key said he did not believe that the public had a right to know why a minister might be removed.
Mr Key said as Prime Minister, he is fully entitled to lose confidence in a minister, and that is a subjective view.
Mr Key said he believed he has acted firmly and fairly and is comfortable with the decision he made.
Police in Wellington have confirmed that a criminal complaint against Dr Worth has been formally withdrawn.
In a statement, police said at no time did they suggest to the woman who made the complaint that she should withdraw it.
The statement said police are assessing the information on the case before they close the file.