In the famous “double indemnity” case, the case on which the book and movie are very loosely based, the murder occured on March 20, 1927 and the murderers were executed on January 12, 1928, less than 10 months later. And that was an extremely high profile murder case.
In their last ditch appeal, the attorneys for the murdering bastards, Saco and Vanzetti, tried to have the sentence commuted because the interval between the verdict (July 14, 1921) and execution (August 23, 1927) constituted cruel and unusual punishment! The sentence was delayed because of the extraordinary circus put on by the defense, nevertheless, even in Texas, six years between verdict and execution would be considered swift these days.
It reminds me of the Nazi saboteurs that were caught of the coasts of FL and NY (I think LI) in June of 1942. They were set ashore by U-Boat, on a mission to blow up military and civilian targets on US soil. They were apprehended virtually immediately, and none had been able to attempt their acts of sabotage, let alone successfully complete them.
They were all tried by military commission (yep, military commission), and all were found guilty. One man, a US national named Quirin became the defendant in the famous US Supreme Court case Ex parte Quirin, 317 U.S. 1 (1942). His life was sparred eventually, as was another US national who was caught. But, the remaining 8 (or 6, I can't remember) were executed as a result of the commission's guilty verdict. They were hanged until death in Washington DC on August 8, 1942 - roughly 9 weeks after they had been apprehended.
Today, we have people at Guantanamo that not only attempted sabotage and murder against America and her citizens, but were actually successful. None have been put to death, almost 10-years later.