Montgomery County State's Attorney Andrew L. Sonner said yesterday that he has reviewed allegations of mismanagement in the Montgomery Police Department and decided that "on face value" the allegations "no not involve matters of criminal misconduct by anybody."

Sonner said he had advised the grand jurors against continuing their investigation of the police department and told them that he was unwilling to petition the court to extend their term for that purpose. He said he suggested they contact Maryland Special Prosecutor Gerald D. Glass. Glass persuaded him to ask the court to extend the grand jury's term, Sonner said, so they could continue their investigation. "I [now] have nothing at all to do with this [investigation]" he said.

Sonner said he told the grand jury that, in his opinion, allegations by an organization called Code 3 that Police Chief Robert J. diGrazia had mismanaged his department were backed by insufficient evidence to warrant a criminal investigation.

He said complaints by Code 3 - which is police terminology for a "serious crime in progress" - seemed to stem from a "difference in philosophy" with the chief over the way he spent police department money and federal grants.

He said no one from his office checked for violation of county administrative procedures, since such violations would not be in the purview of his office.

Sonner added that he expressed his skepticism about the Code 3 allegations to Glass, but acknowledged that Glass, who has met separately with the grand jury on at least two occasions, may be privy to information about the police department that Sonner does not have.

In a report issued Monday, the grand jury said "it is felt that circumstances can exist whereby the state's attorney is not or should not be privy to various information available to the grand jury." The grand jury, therefore, recommended that the law be changed so that grand juries can have the power to ask for extended terms without having to depend on the state's attorney.

Sonner called an unusual press conference yesterday to deny that this comment in the report referred to his handling of the police department investigation. He said that the grand jury foreman, Arthur E. Johnson, authorized him to say that the grand jury was merely speaking "in the abstract" about a legal procedure to which it objected.

In the same report, the grand jury complained that "too many requests for additional information made to the state's attorney office were either forgotten or placed in a low priority." But Sonner said that he had never withheld information about the police department from the grand jury and that his office had actually assisted them in getting the information they requested.

Sonner said he has a good working relationship with diGrazia, but denied he has a "close personal relationship" with the chief.

Sonner and diGrazia recently received a joint $500,000 grant from the Law Enforcement Assistance Administration to set up a program for apprehending career criminals.

Sonar said his portion of the grant was approved Sept. 14. A police spokesman said the police department received word that its portion of the grant was approved on Monday.

This grant, however, was not among those that have been questioned by Code 3. Among its voluminous charges, Code 3 has alleged that diGrazia wasted federal and county money on consultant contracts, showed favoritism in awarding contracts, improperly spent money on travel and training for his officers, and that both the chief and his administrative assistant, Philip H. Marks, wrongly used the department's petty cash fund to pay for various business lunches with citizens, the press or law enforcement officials.

DiGrazia has consistently denied that he has done anything illegal. The FBI, LEAA. the Governor's Commission on Law Enforcement and the Administration of Justice and the county's auditing department have received allegations about the police department and have found no criminal violations.

One county council auditor, however, found that the police department's response to some of the Code 3 allegations was "too vague" and requested further information.