Northwestern District Attorney Elizabeth Scheibel has two State Police detectives and a grand jury helping her investigation into whether a court security officer illegally entered her locked office to retrieve the bathroom key under, instructions from the clerk magistrate for the juvenile courts in Franklin and Hampshire counties, Christopher Reavey, the Boston Globe reported Friday.

Reavey said he instructed a court officer to retrieve the key to a second-floor room for prospective jurors after business hours Feb. 19 so lawyers could use the jury pool bathroom. He called Scheibel's investigation "abusive" and claimed it was driven by a prior bureaucratic dispute over office space.

Reavey said in a March 4 letter that Scheibel was angered in February after he asked whether her staff needed three offices when the juvenile court moved from a Northampton facility to Hadley.

"This I believe is the fuel for this abusive investigation, a smoldering fire which was ignited by the jury pool key debacle," he wrote.