Monmouth AM Nick Ramsay who was arrested on New Year's Day has been released without charge.
The 44-year-old was taken into custody after an incident at his home in Raglan on New Year's Day.
He has since been released and faces "no further action" following an investigation, the force said.
In a statement, Gwent Police said: "We received a report of a disturbance at an address in Chepstow Road, Raglan on Wednesday 1 January at around 20:05.
"A 44-year-old man from the Raglan area was arrested following an incident but he has been released with no further action following investigation."
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