More than a week after the killing of Officer Daryle Holloway, the New Orleans Police Department is still trying to untangle how a handcuffed man riding in the back of a police vehicle managed to fatally shoot Holloway in a brazen escape from custody.

In the meantime, however, the department is retraining its ranks on the importance of frisking and searching suspects for weapons. Officers also are receiving a refresher on the department’s protocols for handcuffing and transporting prisoners.

It remains unclear how 33-year-old Travis Boys got hold of the .40-caliber handgun police say he used to kill Holloway. But even before the department answers that question and others, the retraining is essential to avoid another tragedy, police Superintendent Michael Harrison said Monday.

“We’re not saying that anyone violated policy,” Harrison told reporters outside NOPD headquarters. “What we’re saying is this is what we need to do to be safe.”

The department also announced plans Monday to address an apparent weakness affecting several hundred of its SUVs, including the one Holloway was driving when he was shot.

Boys is believed to have climbed through a sliding Plexiglas opening in the partition that divides the front seat from the caged section of the police vehicle — the section used for transporting suspects.

The NOPD intends to retrofit more than 300 recently acquired SUVs with what Harrison described as a “metal mesh adaptor” screen — a partition similar to those used in State Police vehicles. Officials are still looking into the price of the retrofitting, the superintendent said, but plan to move forward “as fast as we can.”

The department’s older Crown Victoria cruisers don’t have the same vulnerability, officials said.

“It will be a permanent fixture so that we won’t have to use the sliding glass,” Harrison said. “That steel mesh will be a permanent fixture in the car. No one will be able to go through that ever again.”

Particularly in the summer, officers frequently open the Plexiglas in the SUVs to provide ventilation to suspects in custody, who otherwise could become overheated in the back seat, said Capt. Michael Glasser, president of the Police Association of New Orleans.

“It can be extremely hot in those cars,” Glasser said. “It’s not that the cage itself was flawed. The way we installed and designed it was flawed.

“One way or the other, it has to be remedied.”

Glasser said the new SUVs have a number of “documented” vulnerabilities that put officers at risk, which he blamed in part on the design of the vehicles. Another concern, he said, is that a cursory search of the SUVs won’t always reveal contraband smuggled by inmates.

No officers have been disciplined or reassigned in connection with Boys’ escape. The department’s Public Integrity Bureau, however, is investigating whether officers followed proper protocol earlier that morning after arresting Boys on a count of aggravated assault.

Police had seized a .38-caliber handgun from Boys at the scene of his June 20 arrest in St. Roch, where he was accused of shooting at his wife. That gun and the .40-caliber weapon Boys allegedly used to shoot Holloway were found in the front seat of Holloway’s vehicle after Boys escaped, authorities have said.

It’s standard procedure for a single officer to transport a handcuffed suspect to Central Lockup. Officers are required, however, to conduct searches of suspects both after their arrest and when they change custody from one officer to another.

Police also are required to search their vehicles at the beginning of a shift “to ensure it is free from weapons and/or contraband,” said Tyler Gamble, an NOPD spokesman.

Boys should have been searched twice, Harrison said, and “far beyond a frisk.”

“Our policy is clear,” Harrison said. “We just want to make sure that everybody is aware of it.”

Holloway’s family is not angry about his death or “placing blame anywhere,” the superintendent said. “They’re asking me to make sure this never happens again.”

Follow Jim Mustian on Twitter, @JimMustian.