"Merlin's beard, surely we can celebrate one night of the year without worrying about the blessed Muggles"
-- Ms Crook to the Daily Prophet (DP4)
Glinda Crook was a witch who worked for the Campaign for Greater Freedom for Wizards (DP4).
Ms Crook is quoted in the Daily Prophet decrying the actions of the Ministry of Magic, who are introducing new laws designed to reign in the over-exuberant behaviour of wizard-kind on Hallowe'en (DP4)
Other canon notes and references
This was the first use of the mild exclamatory oath "Merlin's beard" in canon.
Glinda was the "Good witch of the South" from L Frank Baum's book "The Wizard of Oz". A crook is someone who steals. Therefore her name seems to be pulling in two different directions....
While the date printed on DP4 is 1 October 1999, the timeframe for these events is 1992-1993.