I volunteered, because why not, but then a schoolteacher volunteered and everyone liked her better. This was actually good, because it turns out the foreman has to carry the indictments over to the court after we're finished, find a judge, and solemnly swear in front of a judge and a District Attorney that these are the True Bills returned by this grand jury. I'm not sure what the purpose of the clerk is. Probably a holdover from some previous life. Once the formalities are over, they start right in on presenting cases.
Grand juries are quite different from regular juries.
Grand juries almost always indict. Basically, if the District Attorney doesn't get an indictment, they're screwing up. They shouldn't be presenting something for which they don't have probable cause. We only had one case where we didn't return a True Bill when we were presented one for indictment. It was a little weird in that they didn't tell us they were deciding not to ask us, but let us think the case would have continued testimony the following week.