If you hypothesize that the person on trial is innocent and declare them guilty, you could make a Type I error, also known as a false positive. This means you incorrectly reject the null hypothesis (that the person is innocent) and accept the alternative hypothesis (that the person is guilty) when the null hypothesis is actually true.
On the other hand, if you hypothesize that the person on trial is innocent and declare them innocent, you may make a Type II error, also known as a false negative. This means you incorrectly accept the null hypothesis (that the person is innocent) and fail to reject the alternative hypothesis (that the person is guilty) when the alternative hypothesis is actually true.
Both types of errors can have serious consequences in a criminal trial, as they can lead to a wrongful conviction or a failure to convict a guilty person. Therefore, it is important to use appropriate methods of hypothesis testing and to carefully consider the evidence before making a decision on guilt or innocence.