There is too much that is unsettling — and unsettled — about the case involving Honolulu Police Department Sgt. Darren Cachola, who will not face criminal charges despite being seen on a surveillance videotape apparently punching his girlfriend until she can’t even stand up.

An internal police investigation concluded there was not enough evidence for criminal charges — though HPD administrative investigations continue — and a subsequent grand jury did not see fit to indict Cachola for the incident. But, the necessity to resolve many exposed deficiencies must not be so easily dismissed.

It must never be OK to accept and condone the kind of beating that was captured on surveillance tape on Sept. 8 at a Waipahu restaurant. Cachola’s girlfriend refused to press charges, saying the two were simply "playing around." But HPD Chief Louis Kealoha’s initial instinct had it right, when he called the violence "unacceptable."

The danger now, with this case fading from public consequence, is that it will make it easier, somehow more excusable, for HPD and others to dismiss domestic-violence calls for help as mere rough horseplay. This simply cannot be allowed to happen.

This case, which led to a legislative hearing on HPD policies on call response and domestic violence protocols, exposed just how subjective these responses can be. Public pressure must continue, in order to ensure that HPD officers are properly trained to follow procedures when responding to incidents involving one of its own, and especially, when they involve domestic violence calls.

As it turned out, the videotape was among the scant evidence for a legal case; a portion has been widely seen, but when viewed in its entirety, HPD says, provides clearer context for Cachola’s punches. In turning the case over to the city Prosecutor’s Office, HPD concluded that there was no complainant, no victim willing to press charges and testify in court, no injuries and no witnesses willing to testify to the event.

The Prosecutor’s Office took the proper path in trying to seek a grand jury indictment, despite criticism to the contrary. Given the volatility of this situation, plus perceptions of closing-of-ranks, it appears that subpoenas for testimony were needed, as well as an objective grand-jury process to weigh the evidence.

With no criminal charges, it looks over — but it’s not. HPD is investigating a serious breach of response protocol, when officers called to the Waipahu incident failed to file a police report — but should have. In the legislative hearing, Deputy Chief for Patrol Operations Marie McCauley said the responding officers will be disciplined. Surely, the very absence of a police report would be a fundamental problem for any indicting grand jury considering evidence, or lack thereof. No paper trail, no case.

Such an omission guarantees protective silence for the alleged abuser, but not for the abused.

Whatever the outcome of HPD’s investigations into Cachola and the responding officers, public disclosure is needed about the discipline taken in this high-profile case. As the law stands, HPD is shielded from any meaningful disclosure; the public has a right to know if an armed officer — let alone a sergeant — has serious violence issues and is getting help. State lawmakers need to change the law for fuller disclosure of details when it comes to disciplinary actions.

As for training, HPD recruits receive three hours of domestic violence-related training, then one hour annually on this subject. That is woefully inadequate, especially considering thatHPD claims to have a zero-tolerance policy toward domestic violence. Further, studies indicate that domestic violence is two to four times more common among police families than U.S. families in general. Training must be tightened to ensure that HPD officers adhere to policies, such as that "cases of domestic violence, including those involving officers as suspects, must be reported."

This whole episode has damaged the credibility of HPD, and legitimate questions linger about above-board handling involving one of its own. HPD is assuring lawmakers and advocates that it will improve its response to domestic violence. That’s got to happen. If anything, efforts must be redoubled to make meaningful reforms in procedures that take seriously the plight of victims and the necessary vigilance to prosecute abusers.