Seven years into a rocky term that includes two high-profile child neglect cases, Administration for Children’s Services Commissioner John Mattingly suddenly resigned Tuesday, but observers say the outgoing commissioner should be praised for pushing for reform and more funds. NY1's Josh Robin filed the following report.

With responsibility for the city's most vulnerable, Administration for Children’s Services Commissioner John Mattingly had no room for error. But on his watch, there were two especially high-profile deaths -- Marchella Pierce in 2010 and Nixzmary Brown four years before.

To watchdogs, Mattingly was responsive, even as his agency was faulted not for preventing the deaths.

After Nixzmary's death, ACS was found to have missed multiple warning signs of abuse. The girl's mother and stepfather were convicted in connection with her death, and 14 caseworkers faced discipline or lost their jobs.

After Marchella died, severely malnourished and allegedly at the hands of her mother, the agency acknowledged it had again missed or ignored signs. Two workers are even charged in her death, along with the girl's mother and grandmother.

However, to Andrew White, co-founder of Child Welfare Watch, Mattingly deserves credit for not deflecting blame and for pushing reform and more funds.

"There's always going to be flaws in child protection services, but one of the shocks to me is that you can spend all of these years working on it, trying to reform practice, and you still find people who aren't necessarily doing their job as well as they should," White said.

Under Mattingly's leadership, according to White, the number of foster placements dropped and more children moved in with relatives. Additionally, the agency started ChildStat, in which every week cases are randomly selected and analyzed.

Mayor Michael Bloomberg said in a statement, "Under John’s leadership, ACS has adapted many essential reforms that have helped to protect and serve the city’s most vulnerable children. On behalf of more than eight million New Yorkers, I want to thank John Mattingly for his transformative leadership and wish him and his family the very best in Baltimore.”

That is where Mattingly is moving, returning to the Annie E. Casey Foundation, which helps disadvantaged children.