The Jailhouse Lawyer by James Patterson

Martha Foster is an attorney and single mother of a 5 year old son with a heart condition. When her law firm changes their benefits to a new plan which will make it impossible for her to provide adequate medical care for her son. When she finds an ad for a public defender in Douglas County, Alabama, she immediately applies. The salary and benefits package is literally an answer to a prayer.
Upon arriving and checking in at the Courthouse, Martha is surprised that there are no cases for her to take on. When she sees an old law school friend who is jailed for failure to appear. Soon she determines that Judge Wyatt Pickens is abusing his authority and runs his courtroom like his personal playground. Martha begins efforts to identify the irregularities and illegal practices. Her efforts lands her in jail for contempt.
Martha files a request for removal for Judge Pickens. She has two witnesses lined up: one a young inmate who has been abused and is unable to pay her court and jail boarding costs, and the widow of the previous public defender who killed himself just before Martha came to town. The inmate backs out on the morning of the hearing and the young widow leaves after watching Martha’s cross examination. Then a surprise witness comes forward.