Supreme Court Chief Justice Salmon Chase. The Chief Justice Chase who ruled the southern secession unconstitutional in the Texas v. White decision? Attorney General William Evarts AG Evarts was part of the team prosecuting Davis. Richard Henry Dana. Dana's concerns with the Davis trial, of which he was also a member of the prosecution, had nothing to do with the legality of secession.
Evarts requested a written legal opinion from Dana, who wrote a letter recommending against prosecution. Evarts had only been considering prosecution in the first place because Johnson had made it a campaign issue and was insisting on it. Meanwhile Chase was doing everything he could to slow the process down. In the end, the prosecution fizzled because Johnson got impeached and so had other things to worry about. Johnson had been the only real driving force behind the prosecution because Davis had treated him like the moron he was when the two of them had served together in the Senate.
At the time all of this was going on Davis was out on bail and was actually touring Europe. His bail had been paid by a group of mainly northerners. One of whom had been one of John Brown's financial backers.
But not because he thought that secession wasn't treason or that Davis wasn't guilty. Dana's concern was that since the trial was to be held in Virginia then it would be hard to convict Davis regardless of the evidence against him, and that might prove embarrassing to the government.
In the end, the prosecution fizzled because Johnson got impeached and so had other things to worry about. Johnson had been the only real driving force behind the prosecution because Davis had treated him like the moron he was when the two of them had served together in the Senate.
It was more Chase than Johnson. Chase was never a fan of the trial, not because he thought Davis was guilty but because he thought a trial would make a martyr of him and continue the divide in the country. With the ratification of the 14th Amendment, Chase decided that a trial and sentence would violate Davis's 5th Amendment rights against double jeopardy. Johnson's last amnesty proclamation killed any chance for a trial.