The Oregon senator asks how many times the DOJ has issued "subpoenas, search warrants, national security letters, or any other form of legal process authorized by a court" to target journalists in leak investigations.

Wyden also asks if the DOJ has made any changes to departmental regulations for investigating journalists since January 20.

Wyden also urges Sessions to further restrict, rather than loosen, the DOJ's ability to seek records from members of the media.

On August 4, Sessions claimed at a press conference that the DOJ has more than tripled the number of ongoing leak investigations compared with the last part of the Obama administration.

Those 2015 revisions "do not go far enough" Wyden writes.

Wyden reminds Sessions that the 2015 revisions came about after the DOJ "abused its surveillance authority" to target the press and expose its sources.

In 2013, the department obtained personal and work telephone records of 20 Associated Press reporters.

Wyden says he wants Sessions to require the DOJ, "absent an imminent threat to Americans' safety," to obtain a search warrant before accessing journalists' personal records.

"Although federal law currently permits the government to obtain historical telephone and email records without demonstrating probable cause to a judge," Wyden writes, "DOJ can and should go above and beyond what is required by statute when investigating journalists."

Related: What Ties Trump to Russia? Ron Wyden Wants Answers

"Journalists play a critical role in our democracy," Wyden adds, "and the chill associated with the government obtaining their communications records in order to identify their sources cannot be overstated."