Chief Minister and Police Minister Lia Finocchiaro’s office said Thursday she was not briefed about the sensational arrest of Labor MP Luke Gosling over the alleged assault of Administrator David Connolly, but has refused to refer the police investigation to an independent agency to mitigate the perception of political interference.

Mr Gosling was arrested at home Thursday morning and taken to the Palmerston watchhouse where he was later charged with two counts of assault on the administrator, which is alleged to have occurred on July 18 at the Darwin Thai Festival, where both men were attending in their official roles.

He has denied the allegations. The assault on the administrator charge carries a maximum 14-year prison sentence if convicted.

Questions have also been raised over the need to arrest Mr Gosling.

Under police general orders, arrests are undertaken only under certain conditions including to prevent the continuation of an offence; to prevent the risk of further offences causing a serious danger to the public; if it is unlikely that a summons will ensure the offender’s appearance in court; and if the person is intoxicated to the extent they would not understand being summoned.

The other condition for arrest is if “the charge is of a serious nature”. Mr Gosling was not charged at the time of his arrest and it is unclear if police thought the alleged assault more than 10 days ago was of a “serious nature” that necessitated an arrest rather than a summons.

Other sources said an arrest can also be used to set particular bail conditions, however the conditions of Mr Gosling’s bail have not been released and it is unclear why that would not have been handled separately after charges were laid.

Lawyer Marty Aust, who represented Mr Gosling during his examination by police at the watchhouse, told reporters he suspected “a degree of politicisation in relation to how this matter is being handled…”

“It’s particularly concerning that the police resorted to the power of arrest when they could have dealt with this matter by way of summons or notice to appear,” he said.

The NT Independent understands the two detectives leading the investigation, who were photographed leaving Mr Connolly’s office last week, are Sarah Firth and Sarah Hutchinson.

Police Commissioner Martin Dole did not respond to questions Thursday about the threshold for arrest or who authorised it.

Media director Mark Wilton said in a statement that police have no intention of referring the matter to an independent body for oversight.

“The Northern Territory Police Force is the law enforcement agency responsible for investigating alleged criminal offences in the Northern Territory,” he said.

“The occupation, public position or political affiliation of the people involved in a criminal investigation does not affect the manner in which an investigation is conducted.”

Mr Wilton added that “allegations that the investigation has been politicised are without foundation”.

Mr Dole was personally appointed by Ms Finocchiaro last year without going through an independent selection process. He became the third NT Police commissioner in two years at the time of the appointment last October.

Ms Finocchiaro’s office did not respond to a series of questions about the perception the investigation and subsequent charges were politically motivated, or what she could do to instil public confidence in the investigation, but said she “did not receive any briefings from the Police Commissioner or any other NT Police officer throughout the course of this investigation”.

Her media director Megan Miller did not respond to a follow-up question about whether the Police Minister felt the matter should be referred to an outside, independent body to investigate given the perception of political interference.