John V. Kelly, acting inspector general for the Department of Homeland Security, stepped down from his post Monday, earlier than he previously expected. The departure followed his office’s rare reversal of more than a dozen reports posted on its website.

“I informed OIG staff this morning that I intend to retire, effective today,” Kelly said in a statement to employees Monday. “I accelerated my retirement because I feel it’s in the best interest of the organization and its employees. As I told the staff, I have truly enjoyed my 11-year tenure with the DHS OIG, an organization with a very important mission and extraordinary staff and managers that successfully execute that mission on a daily basis.”

Deputy Inspector General Jennifer Costello will assume the role of acting inspector general.

Mr. Kelly had previously told OIG staff that he expected to retire on July 31, or as soon as the Senate confirmed Joseph Cuffari, President Donald Trump’s permanent pick for the IG role.

In a special report posted last month, DHS OIG advised it had pulled 13 online reports that praised FEMA’s “efficient” initial response to several natural disasters “despite lacking sufficient and appropriate evidence to support that conclusion.”

The OIG took all but one of the reports offline in March 2018. It pulled the first report in July 2017 after members of the House Oversight and Reform Committee raised questions about its accuracy.

In the special report, Diana Shaw, DHS’s assistant inspector general for special reviews and evaluations, determined that a 2011 change in OIG leadership led to “notable changes” in how the office fielded its Emergency Management Oversight Team. But those changes, Shaw’s team found, “were poorly communicated to staff,” and not well managed by the team’s senior leadership, including Kelly and several former OIG employees.

Following the 2011 shakeup in OIG leadership, “EMO personnel began to think of EMOT reports as ‘feel good’ reports — i.e., generally positive reports that typically concluded that FEMA’s initial response to a disaster was effective,” the OIG reported stated.

Kelly, who oversaw the Emergency Management Oversight Team that produced those reports, recused himself from OIG internal review.

The Washington Post first reported this story on Monday.