There’s no good way to explain the Honolulu Police Department’s questionable handling of an officer’s alleged drunken driving arrest this month. And it’s unfortunate that HPD’s reputation is again under fire.

The department’s image problems start at the top — with Chief Louis Kealoha the subject of a federal grand jury investigation — and one would think the department’s rank and file would take greater care in how it conducts business. But it appears that was not the case in the April 3 arrest of 13-year HPD veteran Brent Sylvester for allegedly driving under the influence.

According to police reports, after rear-ending another car and not stopping, Sylvester refused to take a field sobriety or breath test before his DUI arrest, and after his arrest refused a mandatory blood test — something Joe Q. Public would not have gotten away with. Responding officers should have been more insistent, especially since the law goes so far as to allow police to physically restrain someone to take blood.

While it’s not impossible to convict Sylvester without hard evidence that he exceeded the 0.08 blood-alcohol level, it leaves prosecutors with just a subjective threshold and a much more difficult case.

Police reports said Sylvester, who worked in the Traffic Division, was traveling east on the H-1 freeway near the Aiea offramp about 2 a.m. when his car rear-ended another vehicle. The driver and his two passengers said that Sylvester didn’t stop, so they followed him to his home in Kailua, where he denied hitting them.

The case is another unnecessary HPD public relations problem. Ironically, the incident took place just a few weeks after the department signed a $125,000 contract with a public relations firm to train its two public information officers, leaders and officers to help them communicate more clearly and effectively with the public. The contract also includes research, branding advice, strategic planning and $230-an-hour crisis communications services.

Sylvester’s case presented an opportunity for HPD to let citizens know that it recognizes the seriousness of the incident, and that it is conducting a thorough investigation and will provide the public a full accounting when appropriate. Further, HPD should be disclosing routine protocol in similar incidents or saying if the department will provide more training in handling DUI cases involving its own.

Instead, the department declined comment pending administrative and criminal investigations.

Declining comment and hoping the issue will fade in the public consciousness is a poor strategy. Perhaps it underscores the need for PR training.

Unfortunately, there will be more opportunities for HPD to practice effective communications, especially since a federal grand jury is investigating the chief and his wife, Deputy Prosecutor Katherine Kealoha.

Corruption allegations stem from a June 2011 incident in which Katherine Kealoha’s uncle, Gerard Puana, was arrested for supposedly entering a neighbor’s screened-in porch.

While Puana was at the police station, witnesses said, Katherine Kealoha and police officers entered Puana’s locked home; Puana has alleged that items including documents and cash went missing. The investigation has left a cloud hanging over the department.

It’s critical that HPD recognizes the damage that occurs when it is not forthcoming with information, even more so when it involves its own sworn officers.

The public deserves nothing less than open communication from its police force.