Requiring something like 'intent' makes the picture impossibly murky. Intent can never be established with total certainty. Establishing intent requires mind-reading (ie, is impossible) or a confession that might itself be false.

So intent can only ever be established to some standard of evidence (possible, probable, likely or no plausible alternative interpretation). This introduces a huge amount of uncertainty which starts to dominate the moral situation. The lie cannot be disentangled from what the evidence is that it is a lie; because intent is always a fuzzy concept that cannot be measured or uncovered.

This is where the issues discussed here start to spring from - people imagine different standards of evidence then ask what the moral interpretation of that standard of evidence should be.