Let’s not forget Lincoln the hypocrite.
“...whatever his philosophical leanings, Lincoln went for the cases that would support his practice. This plays out in his handling of cases related to slavery. Though Lincoln was a lifelong opponent of slavery, he would represent the interests of slave owners, such as runaway recovery, when he was paid to do so”.
Below is a review from, of all places, “Salon”.
As he defended a freedwoman and her children threatened with a return to slavery and abolitionists in the "underground railroad" who harbored runaway slaves. Lincoln dealt mostly with technical issues of the law and his performance was regarded as weak, unispired, inadequate. That doesn't justify his taking the case, but he was doing what lawyers do -- if they only represent clients who are innocent and morally without reproach, they wouldn't last long.