While I don't always agree with the view they take, overall I have found them to be pretty politically evenhanded. Even on issues such as capital punishment, you will have respected characters on each side. And they remain on each side, not the liberal winning over the conservative cretin to the correct way of thinking.
My first time watching Law & Order was nearly a decade ago. It was an episode about an abortion clinic bombing. The bombing was plotted by a rabid, raving female pro-life activist who didn't even care that her daughter -- who was secretly seeking an abortion -- was killed in the blast. The way she saw it, she got what was coming to her.
She didn't shed a tear until the prosecutor reminded her that in addition to her trampy baby-killing daughter that was done away with, she had killed her future granddaughter (i.e., an innocent baby). As the story went, that woke her up out of her fanaticism, and she started blubbering on the witness stand.
I was disgusted. I haven't watched the show since.