The comedian tells TMZ ... Janet repeating a claim about Harris that is so easily proven false shows there is malicious intent behind the public smear.

D.L. says Janet is peddling far right lies ... and he thinks it's ironic she's falsely claiming Harris' father is white when there are questions about the Jackson family actually wanting to be white themselves.

For D.L., Janet's trying to be white with her surgically altered nose ... and he thinks this whole racial commentary coming from the singer is rich.

D.L. is also pushing back against Pharrell for saying celebrities should keep their political beliefs to themselves ... D.L. says politics has morphed into pop culture and it should be up to individual celebs on whether or not they want to speak out.

The way D.L. sees it ... every social issue we face in this country has a political remedy, so it's only right to get involved in politics if you want to see change.