Frank Umbriac, Delray Beach Police officer, accused of having sex while on duty

DELRAY BEACH, Fla. - The Palm Beach County State Attorney's Office says a Delray Beach police officer acted improperly with a woman he had investigated.

They will not file charges against officer Frank Umbriac, but they do say he had sex with the woman while he was on duty.

Umbriac had been on administrative leave since June.

Prosecutors wrote a memo to the Delray Beach police chief saying they will not charge Umbriac with any criminal wrongdoing. 

Too many inconsistent statements left them no other choice, they concluded.

The prosecutors' memorandum outlined the incident, which they say happened on June 4th.

Umbriac was on duty when confronting a woman about her noisy behavior.

That encounter allegedly led to sexual intercourse.

But the state said the woman's story changed, at first saying that sexual contact with Umbriac was consensual.

Later, she reportedly said, she would not have had  sex "If Umbriac had not been a police officer threatening her with arrest."

But then another statement,  where she referred to him as a "hot cop," and that she followed him into a stairwell, embracing and kissing him well before the complaint of a sex act.

Prosecutors say they could not prove charges of wrongdoing by Umbriac beyond a reasonable doubt because of the woman's changing statements and the fact that she appeared to be under the influence when making her report to police.

Umbriac remains on administrative leave.

Four Delray Beach police officers are on administrative leave for a separate incident, which is unrelated but still under wraps because it is an internal affairs investigation.