Final answer:
The speaker expresses the emotion of being sorry, as indicated by their acknowledgment of guilt and expression of penitence.
Step-by-step explanation:
The emotion that the speaker expresses in the statement 'I recognize that I broke the law and that this caused great damage to the party's cause. I again admit my guilt and am penitent.' is sorry.
This is evident in the usage of the words guilt and penitent, which indicate a recognition of wrongdoings and a state of feeling remorseful or regretful. The provided references from literature further reinforce situations where characters display feelings of guilt and sorrow for their actions. Expressions of sorrow and apologies are common in literature as an acknowledgment of wrongdoing and the desire to make amends.