I'm taking a class about Nazi Germany and the Holocaust and we are discussing antisemitism throughout history. I've only read the biblical account of Jesus' crucifixion, which puts the blame squarely on Jewish leaders at the time. Reading our class text reveals that that is not the case. Doris Bergen in his book "War and Genocide" even goes to the length of saying this version of events is a "false accusation".
Further research in this subreddit revealed a bit more. In their response here u/gingerkid1234 calls the court the Jewish leaders held a "kangaroo court". But in another thread u/brojangles describes Mark (the Bible character) as being extremely biased in his account of the events since he lived in a Roman city at the time. So with all the historical evidence available, how much blame do the Romans and the Jews each get for the death of Jesus of Nazareth?
If you don't get any good answers here, try r/Academicbiblical
One of the problems in answering your question is that we have no sources describing Jesus's trial from people who were actually there, so all we have is the four accounts in the gospels, which were all written at least 70 or so years after the fact by people who weren't even born yet.
In the gospels, it's not as clear as you say that the blame falls entirely on the Jews. Each gospel has a slightly different version, but in all of them, the Jewish leaders encourage Pilate and don't seem very excited about Jesus, but Pilate and his Roman soldiers are the ones who actually kill him. The Romans were an occupying force in Judea at the time, so they certainly were not obligated to execute everyone the locals didn't like.
Historically, we known that crucifixion was a punishment of Roman courts and not of Jewish ones, so that supports the gospel's account that Roman officials sentences Jesus. But we really have no way of knowing how the Jews at the time felt about it and whether they encouraged it or whether it would have happened regardless of their wishes.