State Supreme Court Justice Joette Katz plans to leave the bench to tackle one of Connecticut’s most perennially troubled government agencies — the Department of Children and Families.

Tuesday morning Gov.-Elect Dan Malloy announced he is nominating her to run DCF.

DCF’s chronic problems have bedeviled governors for decades. A federal judge ruled in September that despite progress, problems remain severe enough to require continuation of federal oversight of the agency.

Malloy said Tuesday he has long admired Katz. “She’s smart, hard-working, hard-charging, appropriately opinionated and holds people to the highest standard.”

Katz was appointed to the state Supreme Court by former Gov. Lowell P. Weicker. She is one of the more liberal justices.

A former public defender based in New Haven, Katz became a Superior Court judge in 1989 (nominated by the last Democratic governor, William O’Neill). Weicker named her to the Supreme Court three years later. She has also taught at Yale, Quinnipiac, and UConn law schools. Among the controversial decisions she has authored: 2000’s State v. Johnson, in which she ruled that shooting a state trooper doesn’t constitute an “especially cruel or heinous” crime—and therefore spared a defendant the death penalty; and 2007’s State v. Bell, in which her majority opinion upheld the conviction of the man who shot New Haven cop Robert Fumiatti (who later died from complications related to the shooting) but found unconstitutional a statute that would have given him a stiffer sentence.

Malloy said her work experience leaves her well-prepared to lead a bureaucracy that has “too often failed our children.”  He added that Katz is currently mentoring four kids in a foster home, which “speaks volumes about her.”

Katz called the move the most important of her career. She said her goals for DCF include reducing the number of kids who end up in foster care. She said she aims to probe why only 18 percent of displaced kids in Connecticut end up with relatives, when the national average is 40 percent.

Malloy said he has already set about looking for someone to replace Katz on the state’s highest court, but he didn’t give a timeline for when that would happen.

Reached after the press conference, Child Advocate Jeanne Milstein called the appointment “a pleasant surprise.”

“I am delighted that the governor-elect appointed someone of Justice Katz’s caliber,” she said. “I look forward to working with her to better serve the needs of Connecticut’s most vulnerable children.”

Sarah Eagan of the Center for Children’s Advocacy, called Katz’ appointment “a new start for Connecticut.”

“It’s definitely a very striking and exciting pick,” she said. “Judge Katz is obviously a brilliant judicious mind and to have her lead this bureaucracy will only lead in a great direction.”