“they.” The ones who hate good and love evil and oppress the poor (Micah 3:2-3).
“he will not answer them.” God does not hear prayers simply because people pray. Everyone sins, but some people are prideful and unrepentant about their sin, and God will not listen to the prayers of wicked and unrepentant people; those prayers are an abomination to Him (Prov. 28:9). It is the prayer of a righteous person that accomplishes much (James 5:16). There are a number of verses that say God does not answer the prayers of the wicked (cp.Job 35:12-13; Prov. 15:29; Isa. 1:15; 59:1-2; Ezek. 8:17-18; Micah 3:4; Zech. 7:12-13; and James 4:3). [For more on God not hearing the prayers of the wicked or honoring their sacrifices, see commentary on Amos 5:22].