Donald Trump Jr. and Jared Kushner were not indicted as apart of Special Counsel Robert Mueller‘s investigation into Russian interference in the 2016 presidential elections, which came to a close Friday.

Don Jr., a top executive of the Trump Organization and an active member of his father’s presidential campaign, and his brother-in-law Kushner, a senior advisor to Trump, were not included in the final indictment list submitted to Attorney General William Barr on Friday. Muller announced last year that he would investigate their involvement in a 2016 meeting at Trump Tower with Russian operatives. In released emails written by Don Jr., it was apparent that the meeting with a Kremlin-connected Russian lawyer was to discuss “incriminating” information Russia had on Hillary Clinton as a part of  “Russia and its government’s support for Mr. Trump.”  Former Trump campaign chairman Paul Manafort also attended the meeting and has been prosecuted on unrelated charges.

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“One of the big-ticket questions was what really happened at the Trump Tower meeting, and you can’t have that unless you interview Don Jr. and Jared Kushner — but Mueller didn’t do that,” said Glenn Kirschner, a NBC News legal analyst and former federal prosecutor. “And why didn’t he do that? It wasn’t an oversight. He’s the most thorough investigator I’ve ever met. That was a tactical measure.” Kirschner believes further investigation by Mueller didn’t occur because there are separate ongoing investigations in New York’s Southern District that Don Jr. and Kushner should be worried about.

Congress is expected to receive the top line conclusions from Attorney General Barr in the next few days, which will be made public.

Although Don Jr. and Kushner won’t be indicted by Mueller, some legal experts believe separate indictments are still a possibility.