Were the Rosenburgs actually guilty of espionage? | AskHistorians Archive Observer

What is the historical consensus of the investigation/trial as it took place. By the standards of the time period, where they found guilty in proper court of law with proper evidence to prove guilt beyond reasonable doubt? Did the state respect their legal rights as per the law in the 1950s.

The government's case against them was not airtight. It relied entirely on the testimony of two shady characters (Greenglass and Gold), and at least one of those (Greenglass) had huge motivations to perjure himself (and later admitted that he did, by exaggerating the role of Ethel, his sister), because the government was letting his wife off the hook as a result (even though his wife was definitely more of a spy than Ethel).

So by that standard, it was not a great trial. I think "reasonable doubt" is a tricky thing, but you could certainly see how some people would doubt the strength of the government's case. In terms of rights violations, they were convinced in a court of law by their peers, and they and their counsel were allowed to cross-examine, give evidence, and so on. The one place, in my non-lawyer sensibility, that there is a possible rights violation is that the government did not make all of their evidence available to the defense as discovery, because a lot of it was classified (see the discussion of VENONA below). Said evidence was not used in the trial, but some of it may have helped exonerate Ethel.

In the seventy or so years since their trial, how much more do we know to support or refute what those in the 1950s knew.

We have lots more information. We have the VENONA transcripts, which were the government's secret evidence they didn't use in the trial (because they didn't want to expose the source), which clearly point to Julius being the focal node in a rather large espionage ring. If that evidence had been introduced in the 1950s I don't think people would have ever considered Julius innocent.

The VENONA transcripts do, however, make it somewhat clear that Ethel was not a major participant (Julius got secret code-names; Ethel was just referred to as "Ethel").

Since the trial we also know a lot more about the full Rosenberg ring, which was much more than atomic bomb secrets (which were actually probably the least useful thing he gave the Soviets). Rosenberg's main ring was centered around military electronics, which was a very important field in WWII and after it — radar systems, fire control systems, and other conventional weapons that allow you to do a lot of useful things for anti-aircraft weapons.

We also have accounts of his Soviet handlers, who said that Julius even was able to give them a full, working copy of a proximity fuze, which was one of the lesser-known "super weapons" of WWII (it is a little radar fuze that can fit on the end of an artillery shell, allowing you to still destroy planes if you miss them, but miss within the blast radius). These Soviet handler accounts make it quite clear that Julius was a dedicated Soviet spy who went out of his way to recruit a dozen or so other people into becoming spies, several of whom went on to be very important (two of the Rosenberg ring spies defected to the USSR after Rosenberg was captured and helped start the Soviet equivalent of Silicon Valley). One can, of course, doubt the total veracity of such ex-KGB accounts — and one should — but the general gist seems pretty plausible, and lines up with what we know about Rosenberg's life and beliefs and work during the war.

We also know that Greenglass later admitted to perjuring himself about Ethel. So that's a big one.

So anyway, it's complicated. Julius was definitely a spy, and not a minor one (even though the main thing he was convicted on — his role in atomic bomb spying — was definitely not his major contribution). Ethel was probably not one. She may have known what Julius did — it isn't totally clear how much he told her — so she may have been legally complicit. But she was no spy. Whether capital punishment of Julius was an appropriate sentence, people can disagree on (I lean towards "no" for practical reasons; one you kill a spy, they can't be of any further utility to you or your nation; a live spy can be eventually pumped for info, or traded for one of your captured spies). Capital punishment for Ethel just seems deliberately punitive: trying to send a message to other potential future spies about what happens if you go down this path.

The government had a stronger case against Julius than it made clear in the 1950s, but it had a weaker case against Ethel than it claimed. So it is a complicated situation. I think the argument that it was entirely due to hysteria is nonsense, but the VENONA records that made this clear were not released until the 1990s, so it was harder to say this before then.