Richard Griffin, longtime deputy inspector general and in recent years acting IG at the troubled Veterans Affairs Department, will leave the federal payroll on July 4, and his retirement is welcomed by some critics seeking a replacement who would be more in tune to whistleblowers.

In a memo to his staff on Monday, Griffin said it was time to end his 43 years of federal service. He praised the staff’s “remarkable record of performance and outstanding achievements.” In the past six years, he said, the IG’s office has tallied:

1,931 reports

11,350 arrests, indictments, convictions and administrative sanctions

$22.5 billion in monetary impact

A return on investment of $36 for every $1 invested

Griffin cited awards from the Council of the Inspectors General on Integrity and Efficiency as well as high scores in the “Best Places to Work in the Federal Government” study by the Partnership for Public Service.

His temporary successor will be Linda Halliday, assistant inspector general for audits and evaluations.

Less enthusiastic about Griffin’s legacy is Sen. Ron Johnson, R-Wis., chairman of the Homeland Security and Governmental Affairs Committee. "During Griffin’s tenure leading the office, the VA OIG failed to make 140 reports public and administratively closed a two-year-long investigation exposing problems at the VA Medical Center in Tomah, Wisconsin," he said in a statement. "My committee has opened an investigation into why the VA OIG inexplicably closed this report and was forced to subpoena Mr. Griffin for documents his office withheld. To date, he has not fully complied with this subpoena."

Johnson repeated his earlier call for President Obama to appoint a permanent VA inspector general.

Danielle Brian, executive director of the nonprofit Project on Government Oversight, who recently joined with a group of VA whistleblowers to call for Griffin to be fired, wrote in a blog: “The VA’s Office of Inspector General is in desperate need of new leadership—the kind of aggressive and independent oversight sorely lacking under Griffin’s tenure.”

She continued: “Instead of being a champion of whistleblowers, Griffin was part of VA’s toxic culture of intimidation and retaliation. When whistleblowers are fearful approaching their IG with information, there is a serious problem.”

As examples, Brian cited a subpoena Griffin’s office issued to her organization seeking background on whistleblowers inside the VA, and an August 2014 incident in which after “Griffin conferred with the VA's then-acting secretary, the OIG issued a final report undermining the claims of a whistleblower who made allegations of phony wait lists and patient deaths at the Phoenix VA Health Care System.”

Griffin has denied allegations that his office interfered with investigations of VA health care facilities. At a Senate Homeland Security panel on June 16, he rebutted charges that his office hid the results of an investigation into prescription practices at a Wisconsin facility, noting that whistleblowers had not faced retaliation.