A sinner does not deserve any respect. His respect amounts to inviting the Wrath of Allah. Hypocrites, innovators in religion, disbelievers, polytheists, atheists, heretics and those who disobey Allah and His Prophet (PBUH) fall in this category, and none of them deserve any respect. It is the Muslims, the pious and those who are faithful to Allah and His Prophet (PBUH) who are worthy of respect.