Senate lawmakers on Tuesday told Veterans Affairs Secretary Robert McDonald to cease his department's retaliation against a whistleblower at the VA Medical Center in Phoenix, Arizona, and to transfer him to a VA facility outside the Phoenix system.

Sens. Chuck Grassley, R-Iowa, and Ron Johnson, R-Wisconsin, told McDonald that since whistleblower Brandon Coleman testified before Congress in December 2014 about problems at the Phoenix facility, he has been subjected to retaliation.

"As founding members of the Senate Whistleblower Protection Caucus, we are committed to ensuring that federal whistleblowers are treated fairly and that whistleblower retaliation is not tolerated within the federal government," the two said in their Feb. 16 letter.

Grassley is chairman of the Senate Judiciary Committee and Johnson chairs the Senate Homeland Security and Government Affairs Committee.

“VA is in possession of the members’ letter and will respond directly to their office,” department spokeswoman Walinda West said. In a statement, the VA said it is committed to creating a work environment in which all employees feel safe sharing what they know, whether good news or bad, for the benefit of veterans, without fear of reprisal.

Coleman is a former Marine and an addictions specialist at the Phoenix facility, where he was suspended previously after informing higher-ups that VA officials and staff were putting suicidal veterans at risk through neglect and poor treatment.

He was one of several whistleblowers invited to testify before Congress in September, when the group talked about the continued harassment that whistleblowers face even as the VA pledges to protect them.

In December 2014, Coleman filed a whistleblower complaint alleging the hospital was failing to properly care for suicidal veterans. A month later, the hospital's interim director, Glen Grippen, met with the VA's regional counsel to learn if they could "remove Coleman from employment," the senators tell McDonald in the letter.

Coleman could not be fired for whistleblowing but could be removed for "unrelated conduct," the attorney advised, according to the letter.

"Shortly after the meeting Mr. Coleman was accused of having an altercation with a colleague" and has been on administrative leave since February 2015, Grassley and Johnson said.

Coleman also reported this past November that a VA employee dressed up as him for a Halloween party at the Phoenix hospital, suggesting that the embarrassing treatment of him has been acceptable to senior officials.

Coleman wants a "simple, fair and equitable remedy," the senators told McDonald. "That remedy is not, as the Department seems to believe, to continue to force him to languish on extended administrative leave at significant unnecessary cost to the taxpayers with no ability, under current law, to challenge his leave status."

He also wants those responsible for the actions taken against him to be held accountable, they said.

The lawmakers also told McDonald they want the VA to brief their own staffs on what the department is doing about whistleblower retaliation. For that, they are requesting all correspondence relating to the investigations into the Halloween incident; to the Office of Accountability Review's inquiry into Grippen's alleged retaliation against Coleman; and to the decision to put Coleman on administrative leave back in February 2015.

-- Bryant Jordan can be reached at bryant.jordan@military.com. Follow him on Twitter at @bryantjordan.