The court did not rule whether, because portions of the search were illegal, prosecutors should be barred from using any of the records in their case against Jefferson. That will be decided by the federal judge in Virginia who is presiding over the criminal case.

The 37 page opinion is here (pdf). The holding is summarized in the opening paragraphs:

The question on appeal is whether the procedures under which the search was conducted were sufficiently protective of the legislative privilege created by the Speech or Debate Clause, Article I, Section 6, Clause 1 of the United States Constitution. ... Given the Department of Justice’s voluntary freeze of its review of the seized materials and the procedures mandated on remand by this court in granting the Congressman’s motion for emergency relief pending appeal, the imaging and keyword search of the Congressman’s computer hard drives and electronic media exposed no legislative material to the Executive, and therefore did not violate the Speech or Debate Clause, but the review of the Congressman’s paper files when the search was executed exposed legislative material to the Executive and accordingly violated the Clause. Whether the
violation requires, as the Congressman suggests, the return of all seized items, privileged as well as non-privileged, depends upon a determination of which documents are privileged and then, as to the non-privileged documents, a balancing of the separation of powers underlying the Speech or Debate Clause and the Executive’s Article II, Section 3 law enforcement interest in the seized materials. The question of whether the seized evidence must be suppressed under the Fourth Amendment is not before us.

We hold that the compelled disclosure of privileged material to the Executive during execution of the search warrant for Rayburn House Office Building Room 2113 violated the Speech or Debate Clause and that the Congressman is entitled to the return of documents that the court determines to be privileged under the Clause. We do not, however, hold, in the absence of a claim by the Congressman that the operations of his office have been disrupted as a result of not having the original versions of the non-privileged documents, that remedying the violation also requires the return of the non-privileged documents.