Iwalani White, the nominee to head the state Department of Public Safety, tried to fend off tough questions yesterday about federal investigations, low morale and debatable decisions in the seven months she has been interim director.

Senators questioned White, a former judge nicknamed "The Hammer," for about three hours over claims that she micromanages the department, doesn't communicate well and punishes employees with a heavy hand.

In her defense, White explained that she is trying to bring order to a short-staffed and backlogged department. She responded to several allegations from staff members that she had retaliated against them based on frivolous complaints.

"I make mistakes every single day," White said. "I mean no harm, but I have to do the right thing. I need to communicate more clearly and more often my reasons for doing things."

About 20 people submitted testimony against White over two days of hearings. But dozens more support her, including Gov. Linda Lingle and Honolulu City Prosecutor Peter Carlisle.

A U.S. Department of Justice investigation recently concluded that Hawai'i violated the constitutional rights of mentally ill prisoners at Oahu Community Correctional Center by putting them in long-term seclusion and failing to adequately monitor them even while on suicide watch.

White responded to accusations that she overreached when she banned Reneau Kennedy, the mental health branch administrator, from Oahu Community Correctional Center.

Kennedy has said she was never told why she was barred or if she was ever cleared of wrongdoing.

"If I were in their shoes, I'd also feel upset if an investigation were opened against me," White said. "I did seriously consider the impact. ... I did not come to this decision lightly."

In another case, Claire Nakamura, the former deputy director for administration, was placed under investigation after one of her subordinates told White that Nakamura had created a hostile work environment.

White stumbled when she said she might put the investigation report through a paper shredder because she considered it a private personnel document.

"Items like that make us think twice about her judgment and decision-making," said Sen. Will Espero, D-'Ewa Beach-Waipahu, chair of the Public Safety Committee. "It sounds suspicious."

Senators also grilled White over the suspensions without pay of five employees who were accused of stealing from the Wo-men's Community Correctional Center. The employees were later exonerated of criminal wrongdoing after a quick investigation.

White's critics testified that she increased her power and control over the department by ordering that all complaints be sent to her office, internal affairs or the attorney general.

"You can't ignore complaints because at the time you receive them, you don't know," White said.

The Senate committee will decide whether to advance her nomination when it meets again Thursday. If approved, White's nomination would go before the full Senate.