Warning to unfaithful men? Err.. yeah but also warning to those who marry in haste - get an emotionally unstable nutcase of a wife/hubby and you're done for.

As for the "upgraded" charge - problem no.1 - she might be able to prove that there is no intention (mens rea). If prosecution cannot prove this, the whole charge gets thrown out and she'll be free. Some of the defences to murder - diminished responsibility (hence the proposed psychiatric evaluation) and provocation (thought hubby having affair and acted immediately). Most probably no MR and/or the DR defence. Provocation won't fly if she had suspicions of the affair earlier and waited for her chance to "teach him a lesson". Still no MR / intention to kill him.

Problem No. 2 - "When she set him alight, Mr Narayan jumped out of bed and knocked over the substance, causing the fire to spread." - This would arguably be a break in the chain of causation. But depends on the evidence collected, how the matter is argued, etc. Depends on a lot of things. If necessary, they'll downgrade the charge to manslaughter.

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Don't want no drama,
No, no drama, no, no, no, no drama