Acts7:58

First the key witnesses presented their evidence to the leaders of the community. The one who was accused always had an opportunity to state his side of the situation. If the evidence of the accusers was considered sufficiently sound, and if the crime merited stoning based on the Law of Moses, the town leaders would pronounce stoning as the sentence.

From there everyone who had gathered would take the guilty person outside the city. This was prescribed in the Law as well, for taking a life inside the city would make the city “unclean.” They always used a place with an elevation difference, preferably about twice the height of a man. The prisoner was bound and shoved to the bottom of the ravine or cliff, etc. They could also throw him over the city wall and throw stones at him from the top of the wall, but that would require having a stash of stones ready for such an event, which is a possibility. We have no way of knowing exactly where they took Stephen but something comes up later that helps us know he was not thrown from the city wall.

The primary witness was the first one to throw a stone, followed by the secondary and tertiary witnesses, etc. In the end, anyone who had a cursory knowledge of the situation and was in agreement with the verdict, could throw a stone. Bystanders who had no knowledge of the situation could not participate. But each “witness” only got one stone. If they missed, they did not get a second chance. If the criminal lived through the stoning, they had to stop trying to kill him. If he was covered with a pile of stones but still alive, he might die from his wounds or from starvation. If relatives were willing to take on some of the shame of the accused, or if they thought he was innocent, they could pull stones off the pile in hopes of uncovering their relative while he was still alive. The death of the criminal depended largely on the number of people willing to serve as witnesses and cast one stone. Therefore, stoning was not 100% certain in its outcome. We get the idea that most of the people who were stoned in the Old Testament era did die, but the possibility of surviving it did exist.

Keep in mind the following facts. Only those inside the chamber of the Sanhedrin had heard the “blasphemy”, so they were the only witnesses that had knowledge of the crime. There were 71 of them but most of them were very old, incapable of throwing a large or medium size stone and very bad at hitting their target with a small stone. But they had lots of authority and they were very, very angry. They really, really wanted this man dead. They thought they had gotten rid of Jesus, but his followers kept doing miracles just like Jesus had. That scared them. And this simpleton’s boldness also scared them. Just like what had happened on Pentecost, this guy was trying to pin on them the death of a man the general populous considered innocent.

We know from the Biblical narrative of the crucifixion of Jesus that the answer is “No, only the Romans could execute someone.”

However, stoning was a unique situation in that death was not assured. When the Romans executed someone, he died. No chance of survival. But in a stoning, the chance did exist and the participants were expected to follow the rules and allow the person to live if that is the way it turned out. So it appears that the Romans may have allowed some stonings to happen because the practice existed in a nebulous legal middle ground. We know the people tried to stone Jesus at one point, Paul was stoned in a different part of the Roman empire (and survived with God’s help), and we have this incident with Stephen. In each of these three cases recorded in the New Testament, the Romans looked the other way.

So why didn’t the Jewish leaders just stone Jesus instead of crucifying him? I believe the answer is that they wanted an assured outcome. They did not want to take the chance of him possibly surviving the stoning. And they did not want His disciples to come at night and dig Jesus’ body out of the pile of stones and claim that he had risen from the dead. Therefore, they pressured the Roman authority (Pilot) to give Jesus a true, inescapable Roman execution.