CHICAGO (CBS) — The investigation into allegations that a suburban police chief stalked his ex-girlfriend is over.

The Cook County state’s attorney’s office says the 10-month probe of Schaumburg Police Chief Brian Howerton is closed and no criminal charges are being filed.

A letter from prosecutors indicates the state’s attorney’s office cannot determine whether Howerton’s alleged behavior was appropriate or professional–only that it was not criminal.

In an exclusive interview with CBS 2’s Pam Zekman last fall, Dawn Davis described her stormy 18-month relationship with Howerton.

“I just remember feeling complete despair,” she said tearfully.

It was an on-again, off-again relationship that she said she tried to end several times. She finally went to Schaumburg village officials for help.

“I just wanted him to stop calling me and following me and to just stop,” she says.

Read About The Second Part Of The Interview Here

CBS 2 obtained a copy of a police report that was then written up by Schaumburg officers as a “stalking” offense. The report accuses Howerton of “harassing” her with hundreds of calls from his village-issued cell phone.

Davis claimed Howerton staked out her house, followed her in his village car to stores and restaurants. She recalled one example when she came out a restaurant called Bonefish and Howerton was in the parking lot — in uniform.

Schaumburg police provided Davis protection as she requested last March when she first went to the village to complain.

Village Manager Ken Fritz says that immediately after Davis filed her complaint, Howerton was told to avoid any contact with Davis. Davis confirms he has.

Howerton denied ever stalking, harassing or threatening Davis.

“That never happened,” he tells CBS 2.

He also said this is his first citizen complaint in 31 years on the force.

“This has been very difficult for me,” Howerton said.