The woman is undoubtedly sincere, but she's also lazy, I guess it's easier to just reflexively give out maximum sentences without actually thinking about the consequences. That's what Roxanne does and what it gets her is an assassination attempt where the hit-man is slain by her bodyguard.
It's all in the why here as after awhile going through some more obvious suspects Jerry Orbach and Jesse Martin settle on some poor accountant who made a killing with insider information. As a first offense this guy who was beautifully played by David Wohl who is the personification of a nebbish would have gotten at most time in some country club, maybe even witness protection if he had other information on bigger fish. But when Hart hear that Wohl's wife made a fast trip to the Caymen Islands, she goes ballistic and sends him to Riker's Island.
In Riker's Island, not being a man used to the criminal justice system, the poor slob gets played a few mind games which result in the crime. Sam Waterston with defense attorney Tovah Feldshuh do try and work out an equitable solution which I believe they do.
What's best about this episode is the final confrontation scene with Dianne Weist and Roxanne Hart. Weist was only on for a short while as the appointed District Attorney after Steven Hill left the series. But I believe this episode was her finest hour. When Hart hears that the 'mastermind' behind her attempted murder was cut a deal she goes ballistic. Weist calmly and professionally puts her down saying that when Hart just starts handing out maximums she makes it tough on everyone else and she bears some responsibility here as well. Not a message she wants to hear, but a message well aimed at so called 'tough' judges.