一个关于英语和法律的问题,非常希望能得到大家的帮忙,在下感激不尽!3Q!3Q!3Q!3Q!3Q!3Q!

一个关于英语和法律的问题,非常希望能得到大家的帮忙,在下感激不尽!3Q!3Q!3Q!3Q!3Q!3Q!
“At common law,and in many states,a grand jury can return charges in either of two ways.One is to vote on a set of charges submitted by a prosecutor; these charges are contained in a proposed indictment,and if the grand jurors decide there is probable cause to support the charges,they vote a "true bill," that is,they vote to return the indictment and initiate a criminal proceeding.If the grand jurors decide there is not probable cause to support the charges,or that the charges should not be pursued for other reasons,they vote a "no true bill," which means the indictment is not returned and no criminal case ensues.”在这段话中,既然juror vote a"true bill",为什么还要“return the indictment ”呢?而一个“no true bill”为什么是indictment is not returned 案件不予受理,不是应该驳回起诉么?难道说起诉书不返还就表示法院不予受理么,反之,才是决定受理案件么?非常疑惑,在下感激不尽!