The chief of staff for former Virginia first lady Maureen McDonnell kept hidden from her boss and the former governor extensive efforts she undertook to get a job with the Richmond-area businessman at the center of the federal corruption case against the couple, new court filings show.

Mary-Shea Sutherland tried to arrange leaving state employment and going to work for Jonnie R. Williams Sr. — perhaps as a personal assistant or perhaps at a public relations firm where Williams would be a key client, court filings show. The two exchanged nearly 200 text messages and 80 phone calls in 2011 and 2012, and Sutherland wrote in a draft letter to Williams that she kept copies of the messages secret from Maureen McDonnell.

“If I had kept copies of those in my desk she would have had quite an eyeful,” Sutherland wrote in the draft letter.

Defense attorneys representing Maureen McDonnell and her husband, former Virginia governor Robert F. McDonnell (R), have argued previously that Sutherland’s relationship with Williams, in some ways, undermines prosecutors’ case against their clients.

The McDonnells were indicted this year on charges that they arranged meetings for Williams, invited him to events and performed other favors for him and a company he used to run in exchange for gifts and money. But defense attorneys have said that Sutherland organized at least one event — an August 2011 lunch at the governor’s mansion — while she was planning to leave her chief of staff job and work in some capacity for Williams.

The court filings made public Wednesday show that Sutherland’s relationship with Williams was more extensive than was previously known. In a Jan. 20, 2012, letter from Sutherland to Williams — a letter that was apparently drafted but never sent — Sutherland poured out her unhappiness with how her employment at the mansion had ended and wrote of keeping her contact with Williams secret from the first lady.

“You were insistent that I not tell the Governor’s Office I was leaving until after the luncheon at the Mansion for the doctors,” Sutherland wrote.

Sutherland also wrote of her confusion about Williams’s relationship with the McDonnells. “Even today when you called me you told me how badly the McDonnells treated you and yet I know that you continue to lend your plane and that you even had lunch at the Mansion yesterday,” Sutherland wrote.

In the letter, Sutherland appears to have emerged feeling jilted by both the first lady and by Williams. She wrote that the dietary supplement executive repeatedly promised to find her a job but never delivered. The McDonnells’ attorneys have indicated that undermining Williams’s credibility will be a key part of their trial strategy.

The draft letter does not spell out specific actions — if there are any — that Sutherland took to help Williams or his company while she worked for the first lady. And the document itself is hardly a silver bullet for the McDonnells’ defense. Prosecutors have noted that Sutherland left her job in October 2011, before the majority of payments Williams made to the couple.

Defense attorneys hope to convince a federal judge to allow them to subpoena more records related to Sutherland and Williams’s relationship — one which seems to have soured.

Sutherland wrote in the letter that when Maureen McDonnell got wind of her communicating with Williams, the first lady “forced me to give her the password to my computer so she could look for evidence.”

“I feel that I am owed an explanation of what really happened and if you were the one that told the First Lady and started that avalanche — I want to know why,” she wrote.

Attorneys for Sutherland and Williams declined to comment.

Rosalind S. Helderman contributed to this report.

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