My sister is a lawyer who works with poor clients with criminal cases (though not a defense attorney). She believes strongly that most people are better off with their public defender than with private council. I asked her if she could square this with the general perception that the criminal justice system is stacked for with wealthy, she answered that the, most of the time, the connections matter more than the actual money. There are a lot of bad private lawyers out there, and it's hard for most people to tell them apart from the good ones. For a lot of us here, if we suddenly need a lawyer, then we'll ask our friends and family to help us find a good one. But if you don't know anybody who knows anybody who knows a lawyer, what do you do? Look at online reviews? If I were freaked out about criminal charges, needed a lawyer now, and didn't have my connections, it'd be up to blind luck. That's the reality for most criminal defendants.

They'll hire private council and think that because they're paying for it, it's better. But it's often not. For a typical defendant with an aggravated assault charge, a public defender has handled dozens of similar cases before. Moreover, they'll have done it with your judge and your prosecutor. A private lawyer probably won't have that. Granted, this probably holds a lot less for the HN comments section.

I'll add that there is no right to defense council for civil cases. These can have consequences just as dire as a criminal case, as in immigration or eviction proceedings. An indigent defendant with no lawyer has a very poor chance. There's a movement to create this right [1]. The current Supreme Court, however, seems more likely to weaken Gideon v. Wainwright than expand it.