I don't think any lighting would have made a difference.

The cop was obviously driving dangerously fast, not paying any attention to where he was going, probably drunk, but definitely drunk enough on his own self-worth to think the law didn't apply to him (assuming he even "bothered" to know the law).

To blame the other boat's lighting is his arrogant way of denying his responsibility for the incident. The crooked DA is playing along with the ruse, just to protect his buddy and cover up the blatant abuse of power the sheriff's department committed.

The deputy deserves to be strung up, the DA should be dis-barred, and the other deputies who refused to take witnesses' statements, or give the killer cop a breathalizer, should all be fired. The whole rotten bunch should definitely be charged with obstruction of justice.