The only people I know who do not sin are God the Father, God the Son, and God the Holy Spirit. (Of course the elect angels also are in that category.)
All the others who claim not to sin have either scarred their souls so much that they arrogantly ignore their sin or those who feel so very proud about how sinless they have become, that they also have fallen into sin.
1 John 3:7-15
King James Version (KJV)
7 Little children, let no man deceive you: he that doeth righteousness is righteous, even as he is righteous.
8 He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil.
9 Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God.
You can try and wiggle yourself out of John’s real insights here...but it will not work.