Donald Trump's impeachment shows small countries such as New Zealand there are consequences for international leaders breaking the rules, a University of Otago academic says.
Yesterday, accused of abuse of power, and obstruction of Congress, Trump became the third United States president to be impeached.
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Whether he is ejected from office is now in the hands of the Republican-controlled Senate.
University of Otago politics professor Robert Patman said New Zealand had a "huge interest" in the saga.
"Anything which makes the rules work is important for a small country. No-one should be seen as being above the law."
It was clear Mr Trump deviated from his country's law in his dealings with Ukraine President Volodymyr Zelensky, he said.
The first of two charges against Trump relates to the allegation he attempted to coerce Zelensky into smearing political rival Democratic presidential contender Joe Biden in return for military aid.
"I think that's important what's happening because Mr Trump has clearly acted in a way that is at variance with the US constitution."
As countries such as New Zealand had relatively low international sway, they were helped by any sign showing there were consequences for leaders breaking the law.
Although New Zealand had populist leaders, its political system made it more difficult for them to become prime minister.
Here, a coalition needed at least 48 per cent of the popular vote, Prof Patman said.
"If they had that in the UK, Boris Johnston, with his landslide victory, would be scratching around with 43 per cent of the vote, trying to find coalition partners."
There was no certainty Trump would be removed from office, Prof Patman said.
"The Republicans are still behind him, which is extraordinary."
However, while the impeachment might energise Trump's political base, it would at least show others that something was being done about his behaviour.