The RSPB is the subject of a criminal investigation by a local council in Dorset for the alleged felling of protected trees on a private golf course.
The charity allegedly felled 36 pine trees in order to create heathland on Parkstone Golf Course near Poole after applying for a felling licence from the Forestry Commission.
But the trees were legally protected and their removal has prompted a criminal investigation by Poole Borough Council into the charity and the golf club.
The Charity Commission has also confirmed that it received complaints about the matter.
A statement from the charity said the felling was carried out "as part of our long-term commitment to the restoration of heathland in Poole and beyond".
The statement said: "We are aware that the Borough of Poole is conducting an investigation into this matter; until full details of this investigation are known it would be inappropriate for us to comment further."
Andy Dearing, enforcement team manager at Poole Council, said both the charity and the golf club were being investigated "for causing or permitting the destruction of up to 36 protected trees on the site of the golf club in December 2018 as this is contrary to section 210(1) of the Town & Country Planning Act 1990".
He said this could result in an unlimited fine on conviction and proceeds of crime penalties if the prosecutor could demonstrate a financial gain to the defendants.
A spokeswoman for the Charity Commission said: "We can confirm that we have received complaints about the involvement of the RSPB in the felling of trees at Parkstone Golf Club.
"We will be assessing information, including any findings from Poole Borough Council’s investigation, to ensure the trustees are complying with their legal duties and responsibilities towards the charity."