Three resignations in Todd Barclay's Clutha-Southland electorate since the start of the year have raised questions about the MP's relationship with his staff and party members.

Several people connected to embattled Clutha-Southland MP Todd Barclay's electorate have been approached by police for interviews, while Parliamentary Services has confirmed it has also spoken to police.

Three resignations in Barclay's Clutha-Southland electorate since the start of the year have raised questions about the MP's relationship with his staff and party members, and the involvement of the police could put his position under further threat.

Gore-based senior electorate agent Glenys Dickson resigned in February, with a party official citing an "employment problem" between the pair.

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*National party Clutha-Southland chairman Stuart Davie resigns

*Clutha-Southland MP Todd Barclay's senior staffer resigns

*Clutha-Southland MP Todd Barclay's Queenstown staffer also resigns

Later that month, National's Clutha-Southland electorate chairman Stuart Davie resigned, saying it was "untenable" for him to carry on, while Barclay's Queenstown-based electoral agent Barbara Swan resigned in January, reportedly to spend more time travelling and with family.

Swan told the Otago Daily Times that police had arranged a meeting with her, but that it had been postponed and she had "no idea" what it was about.

Swan would not repeat her comments when approached by Stuff.co.nz, referring enquiries to Parliamentary Services.

However, it is understood that police have made contact with several people in the electorate as part of their enquiries.

The police involvement is believed to centre on a complaint about the "employment issue" which led to Dickson's resignation - understood to relate to unproven allegations of a secret recording made by Barclay.

A spokeswoman for Parliamentary Services, which employed Dickson, confirmed police had been in contact with the organisation regarding Barclay, but said it would be "inappropriate" to make any further comment.

A police spokesman declined to comment, saying: "In general, we do not respond to requests which seek to confirm whether specific individuals are the subject of police complaints or enquiries."

Davie and Swan declined to comment, while Dickson did not respond to enquiries.

Barclay said he had not been contacted by police in relation to any complaint, adding: "If they do contact me on any matter, then I will co-operate fully."

A spokeswoman for Prime Minister John Key said: "The Prime Minister is aware of a difficult employment dispute but it is not his intention to comment on what may, or may not have arisen out of that."