PHOENIX — A state judge refused Tuesday to block the Citizens Clean Elections Commission from investigating whether Attorney General Tom Horne used public resources and staff in his current reelection bid.

Maricopa County Superior Court Judge Dawn Bergin rejected Horne’s contention the commission has legal authority only over candidates who “participate” in the public funding system and run for office with public dollars. His attorney, Mike Liburdi, pointed out Horne is using donations and family money to gain the Republican nomination.

But Bergin said the plain language of the law “demonstrates an intent to subject nonparticipating candidates who substantially exceed the statutory contribution limits to the same penalty as participating candidates: disqualification or forfeiture of office.”

Bergin was no more sympathetic to Horne’s argument that letting the commission investigate his activities means he would be subject to multiple investigations by multiple agencies. She said her job “is not to make policy determinations, but to construe statutes according to their plain meaning.”

The judge acknowledged the Legislature this past session amended the law to spell out the commission “has no authority to accept, investigate or otherwise act on any complaint” involving a violation of election laws.

But Bergin pointed out that law did not take effect until July, after the commission started investigating Horne. And she said there was nothing in the law that said it was retroactive.

Sarah Beattie, a former staffer at the Attorney General’s Office, has charged that she was asked and expected to work on state time on Horne’s reelection bid. Beattie also said she saw others doing campaign work in state offices.

The Secretary of State’s Office already has concluded there is reason to believe the law was violated.

The Maricopa County Attorney’s Office also is looking into whether there were violations of other statutes about misuse of public funds.