The Corrective Services Minister Murray Cowper has been forced to defend allegations he was involved in illegal land clearing at Wedge Island.
Mr Cowper says he was among a group of people using a small earthmover to remove a pile of sand piled up next to a shack that he part owns in January when they were approached by a Department of Environment and Conservation officer.
He says the officer informed them they may be in breach of land clearing laws.
"We weren't aware of that situation, it was only a new bit of information that came out just prior to Christmas," Mr Cowper said.
"Had we done this a few weeks before we wouldn't have been in contravention to the best of my knowledge.
"We remedied the situation and we've now sought to make the proper application."
Mr Cowper says he has not heard from the DEC since the incident and is not sure whether an investigation is underway.
The Department has since confirmed it is examining the incident.
It says the maximum penalty for illegal land clearing in WA is a $250,000 fine.
Mr Cowper says he has raised the issue with the Environment Minister Bill Marmion.
"This is a problem not just as demonstrated with me, this is an issue for many people, particularly farmers, who have been concerned about falling foul of the law inadvertently. I think this is what's happened in this case," he said.
The Premier Colin Barnett says Mr Cowper has not spoken to him about the issue.
"I don't know the circumstances of what is claimed," he said.
"I'm a pretty reasonable person, obviously if there is any issue involving a minister I will find out what has occurred but I'm not going to pre-judge the situation."
State Opposition MP Ben Wyatt says Mr Cowper should be sacked.
"These are serious offences that a Liberal Cabinet minister appears to be under investigation for," he said.
"I refuse to believe it was an innocent mistake and I find it incredible that the Premier says he knew nothing about the investigation."