President Trump’s outside advisers — individuals who are not employed by the federal government — may now be protected from future congressional and legal investigations, according to a new opinion from the Justice Department’s Office of Legal Counsel. 

In a 21-page opinion published Monday evening, the Office of Legal Counsel told the White House that the president can move to extend executive privilege, the right of the president to contain confidential communications within the executive branch, to advisers who do not work for the White House, but who provide him with direct advice. 

The new opinion says that executive privilege can apply to private advisers of the president if the communications “relate to official presidential decisionmaking,” are confidential, and involve conversations between the president and his direct team of advisers. 

The opinion, which is not binding, comes months before a contentious midterm election that could result in Democrats winning one or both houses in Congress. If that were to happen, a barrage of investigations could follow and may expand the number of individuals potentially protected from future testimony or investigation.

Executive privilege is often asserted by the president in conversations with executive branch staff, like lawyers who work for the White House, but the new step could protect Mr. Trump’s outside legal counsel and other advisers from divulging information in future congressional investigations or legal proceedings. 

“At bottom, the purpose of executive privilege is to protect the government’s decisionmaking processes,” the opinion said. It was signed by Assistant Attorney General T. Elliot Gaiser, who leads the Office of Legal Counsel. 

“The need for presidential confidentiality applies to communications with private advisers just as it does with government officials. A President might determine that a private adviser has unique insight or experience, and that full knowledge about a contemplated decision cannot be obtained through consultation with only government employees,” the opinion continued.

This is not the first OLC opinion by Mr. Trump’s Justice Department that has broken with historical precedent.

In April, Gaiser authored an opinion that said the federal law enacted in the wake of the Watergate scandal that requires the president to preserve certain documents and turn them over to the National Archives at the end of his administration is unconstitutional, and that Mr. Trump does not need to comply with it. 

Weeks after the opinion was published, a federal judge in Washington, D.C. ordered White House staff and President Trump’s top advisers to comply with the law after a government oversight group and the American Historical Association sued to invalidate the opinion. 

The opinion could also shield outside Trump adviser and lawyer Boris Epshteyn, who was recently subpoenaed by the American Bar Association in a lawsuit filed last year related to the White House’s alleged “intimidation policy” against major law firms that resulted in executive orders targeting four firms and deals made with several others. 

The American Bar Association is seeking communications between Epshteyn and the White House, and the DOJ has moved to quash the subpoena, arguing Epshteyn “provided the President with privileged and confidential advice in connection with the Executive Orders at issue.”