can be used at the beginning of a setence: I think. Therefore I am. 我思う。ゆえに我在り。
The second clause cannot usually be in the past tense, unless the result (2d clause) is ongoing. So, になった is OK for the predicate because it tells of the circumstances today.
I have my doubts about example 7888 because it is past tense and the proving has finished. So, I think "yue ni" cannot be used here. However, if the predicate were "yuuzai hanketsu ni natta" or "yuuzai de aru" ("is a guilty verdict" or "is guilty"), it may be grammatical. The second clause cannot be a completed action, per Dictionary of Advanced Japanese Grammar p.747. Examples 7889 and 7890 are copied from that book verbatim and should be credited to it.