Amid Democrats' push to subpoena the full, unredacted Mueller report, Fox News senior judicial analyst Judge Andrew Napolitano explained why Attorney General Bill Barr cannot disclose every single detail.

In a four-page letter to Congress last month, Barr said Mueller did not uncover evidence of collusion and reached no conclusion on whether Trump obstructed justice during the investigation. Barr has said he will release a redacted version of the report by mid-April.

Despite that, House Judiciary Committee Chairman Jerrold Nadler (D-N.Y.) announced plans to vote this week to authorize subpoenas to obtain the full Mueller report. House Intelligence Committee Chairman Adam Schiff (D-Calif.) has also called for the full report to be made public and doubled down on his claim that Trump and his administration colluded with foreign powers.

On "Fox & Friends" Tuesday, Napolitano explained that Barr "cannot legally" release grand jury material, in accordance with section 6(e) of the Federal Rules of Criminal Procedure.

"If the government has materials about a person who's not being charged, it can't release them," Napolitano said.

He added that Barr also cannot release information about ongoing investigations or classified materials, predicting that "roughly half" of the 400-page report will be redacted.

He said Democrats want the full Mueller report and "millions" of underlying documents -- including any possibly negative information about President Trump -- for political reasons.

"They want to second-guess Bob Mueller and the attorney general," Napolitano said.

He noted that Trump has said he has nothing to hide and called for the full report to be released, which Napolitano called potentially "troublesome."

"That could be considered a waiver of his right to privacy. It depends on how a federal judge wants to view it."

Watch more from the judge above.

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