ESPN commentator Stephen A. Smith has made a habit of going against the grain on controversial issues -- and he continued that trend on Tuesday.

Weighing in on the divisive "black lives matter" movement, Smith asked Twitter why there's not outrage among "black lives matter" advocates when "black folks are killing black folks."

(Twitter)

He then defended Democratic presidential candidate Martin O’Malley for proclaiming "all lives matter." The Democrat was booed by demonstrators and was later forced to apologize for saying all lives matter.

"I'm a black man. Of course I know #BlackLivesMatter," Smith wrote. "You can't boo a presidential candidate just b/c he says 'all lives matter'."

Read Smith's remarks below:

Where is all the noise about #BlackLivesMatter when black folks are killing black folks?

— Stephen A Smith (@stephenasmith) July 21, 2015

There's nothing wrong when a presidential candidate says "All lives Matter"!

— Stephen A Smith (@stephenasmith) July 21, 2015

I'm a black man. Of course I know #BlackLivesMatter. You can't boo a presidential candidate just b/c he says "all lives matter".

— Stephen A Smith (@stephenasmith)

July 21, 2015

I didn't hear Gov. Martin O'Malley's interview. And I'm not debating the significance of "Black Lives (cont) http://t.co/UAYjyUm2IP

— Stephen A Smith (@stephenasmith) July 21, 2015

Smith was called an “idiot,” “coon,” “clown,” “sell out” and much more for his opinion.

Former CNN host Piers Morgan also got into an exchange with Marc Lamont Hill over the issue.

ALL lives matter. > RT @marclamonthill ALL black lives matter.

— Piers Morgan (@piersmorgan) July 21, 2015

Despite backlash from Hill and others, Morgan stood his ground.

Is saying ‘All lives matter’ really that contentious? I mean, REALLY?

— Piers Morgan (@piersmorgan) July 21, 2015

(H/T: Mediaite)

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