In 5:19 we see the Koen dealing with the Sotah woman and making her take an oath that she did not sleep with the accused man and the bitter waters will thereby be cleansed of the curse.
Rashi says that we state the oath by saying to swear that she did not sleep with the man and is clean, and we do not mention the other possibility - that she did sleep with him and is guilty and will get her punishment. Rashi says that when dealing with life or death laws, we begin with the zechut and not the chiyuv, even though it is obvious to all.
We are to look for optimism and merit all the time. Even when, or especially when , dealing with such serious matters. A persons attitude can make all the difference. If we go into the judgement or any situation we are dealing with with an attitude of optimism, the chances of success are greatly improved.