Jamie, moral or ideological reasons were certainly included in the northern abolition laws. It was no coincidence that all of these states passed laws against slavery (or setting in motion its end within their borders) during and immediately after the American Revolution. Talk of "liberty," "freedom," and "independence" highlighted the hypocrisy of slavery (a point the British were sure to emphasize) and led to a strong movement against slavery in the North and Upper South. Upper Southern states considered emancipation, but ultimately decided against it. Nonetheless, many Americans from Virginia upward chose to free their slaves during that period, even if their respective states did not enact formal emancipation. (Which is why the free black populations of Maryland and Virginia were so large in the early 19th century.)