Psalm 51:5 (Guilt or Iniquity?)

Hebrew (Leningrad Codex): הֵן־בְּעָוֹ֥ון חֹולָ֑לְתִּי וּ֝בְחֵ֗טְא יֶֽחֱמַ֥תְנִי אִמִּֽי׃

NET: "Look, I was guilty of sin from birth, a sinner the moment my mother conceived me."

ESV: "Behold, I was brought forth in iniquity, and in sin did my mother conceive me."

The Hebrew word avon sometimes bears the meaning "guilt," but it may also denote iniquity or punishment for iniquity. 

Compare Jeremiah 2:22 (NET), but see the translation's notes. Cf. Romans 7:18-20. BDB makes the point that it's hard at times to distinguish the concept of guilt from iniquity when it comes to the Hebrew avon. NWT 2013 opts for the "guilty" aspect of the word.

https://www.academia.edu/99185796/_Indeed_I_was_born_guilty_Reading_Psalm_51_7_in_a_Canonical_Context?rhid=27729000667&swp=rr-rw-wc-37767435