[Ichneumon]

Harrison, the district prosecutor devoted to truth and the law over public perception (which is implicit, although never overtly stated about his personality.

This sentence no verb.

[G. Stolyarov II]

Here is the full sentence (you had only posted half of it):

Harrison, the district prosecutor devoted to truth and the law over public perception (which is implicit, although never overtly stated about his personality. There would have been a worthy character for the film to dwell on, but he is afforded no more than two to three minutes of attention) is framed by Flynn, who fabricates Roxie’s diary and places it into the hands of Harrison’s witness to subsequently be exposed for its evident artificiality.

Yes, there is a sentence within a sentence, but this is acceptable due to the fact that it is contained in parentheses. Any further grammatical concerns?