They make the king glad with their wickedness,
And the princes with their lies.'
We might cite here ‘like people, like king'. For as the people carry on in the ways of sinfulness and apostasy, and especially in whoredom after the Baalim, their kings are delighted with them, and their princes delight in their false behaviour. They are all one together in their rejection of the true covenant of YHWH. The princes may include the leaders of the ‘ten tribes' (compare Numbers 1:16) and also the king's advisers and generals.
Others see a reference here to court intrigue with the king seen as being pleased with those who have brought about the overthrow of his predecessor by wickedness and lies.