National Labor Relations Board (NLRB) Acting General Counsel Lafe Solomon is in hot water.

On Thursday, NLRB Inspector General David Berry released a report in which he accused Solomon, who has been the board’s acting GC since June 2010, of participating in a case in which he had a financial stake.

The case involved the social media policy of Wal-Mart Stores Inc., in which Solomon owned more than $15,000 in stock. According to the report, the NLRB’s ethics rules bar NLRB employees from participating “substantially” in matters in which they have financial interests.

The Education and the Workforce Committee and the Oversight and Government Reform Committee disclosed Berry’s report to the public on Friday.

The report says Solomon disclosed his Wal-Mart stake to the NLRB’s deputy general counsel in early January and acknowledged that he would need a waiver in order to participate in the Wal-Mart social media case. Solomon attended a meeting about the case before seeking a waiver. The waiver was denied. Solomon later sold his Wal-Mart stock.

At the meeting about the case, Solomon agreed with the NLRB that Wal-Mart’s social media policy was overly broad and violated federal labor law. However, he did express concern that the NLRB would face flak if it filed a complaint against the retailer. He suggested the NLRB reach out to Wal-Mart to see if it would amend its social media policy before the agency took steps to file a lawsuit. In the end, Wal-Mart did change its social media policy without the NLRB having to file a complaint.

Berry’s report says that though there isn’t any evidence that Solomon acted with intent to achieve financial benefit, he did participate in the Wal-Mart case knowing that he owned stock in the company and that the case “would have a direct and predictable effect on that financial interest.”

But Solomon’s lawyer told Berry in a letter on Friday that he reached the “wrong conclusion” and that Solomon “didn’t commit even a technical violation of applicable ethics rules.”

According to the Wall Street Journal, it’s unclear whether or how Solomon could be punished for his actions.

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