Saint Cad, why you focus on Mary Surratt, and not mention Dr. Mudd is beyond me. Frankly, given the evidence I’d read when I first got interested in the Lincoln assassination it seemed pretty clear she knew that Booth was in Washington for something to aid the Confederate cause,a nd that she and her daughter had been active in espionage for the Confederacy. It is less clear whether she knew he’d intended to murder Lincoln. Having said that, Dr. Mudd was hanged for the crime of treating a man with a gunshot wound, before the outlaying town he was in had been notified of the Assassination of the President. Personally, I don’t see the Mary Surratt’s death was a gross miscarriage of justice. I do think that Dr. Mudd’s was.
On a personal note - during my time in service I saw one incident that supports bluethree’s cite. A man was found dead in one of the shipboard offices, apparantly strangled with the cord of a telephone cord. It was ruled a suicide, and the workspace was ordered cleared before any serious investigation was done. (IIRC within about two hours of the body being found.) The family tried, for years, to find anyone to talk to about their theories for who may have murdered him instead, but none of the theories I’d heard made any sense to me. (Their favorite suspect was someone whom I had trouble imagining doing any of the things that they accused him of doing.) Which doesn’t make the official story any less fishy looking. It’s possible, but no one can come up with a convincing reason for suicide, either.
A less drastic miscarriage of justice involved another friend of mine. Our ship’s engineering department had something of a morale problem. Anyone who knows the US Nuclear Power program knows that any time something goes wrong there is a lot of pressure to provide a single person at fault. This has the potential to evolve into a witch hunt, and not a serious investigation of what went wrong. The new ship’s XO came aboard and decided he’d do something about M-DIV’s morale. So he arranged interviews with everyone in M-DIV and prefaced each interview with a promise that nothing said during said interviews would be punished. Well, one of my buddies, who’d been in for about 5 years, was a bit tense talking to the XO. So, LCDR Dixon (His real name. He knows no one on the Virginia at that time will ever trust him again.) asks why my buddy was mad. He replied, I’m not mad, just tense. So the XO asked for an explaination. And reminded my buddy of the promise of no repurcussions. So my buddy said, I just don’t like officers.
Within 24 hours he was off the ship.
I’m not saying I expect the XO to have been happy hearing that statement. But with all the promises made, he shouldn’t have acted on it.
Instead, my buddy was denuked - that is he lost his nuclear power plant operator classification, which meant his pay dropped $275 a month, and transferred to another ship as soon as the paperwork could be completed. Which was about a week after he was taken off the ship. Just to make things even more infuriating, this was during a period of no effing mail, because, we were told, they couldn’t get a supply ship down to us. But they got one to take my buddy off, and still no <censored> mail.
Let’s just say, as a means of fixing M-DIV’s morale problem, this tactic failed miserably.
Oh, and I don’t much trust officers, myself, now. 
