I really can't believe some of the comments on this string. Seriously, how can you guys really be that dispassionate and clinical?
Imagine that the dude who got beat down was your dad.... or your little brother. Still think the prosecutor shouldn't file charges?
This (insert various profane adjectives) prosecutor should resign in shame for being such a (insert various profane adjectives) bitch. Gutless (insert derogatory & profane noun) - your job is to seek justice! Period.
The District Attorney is the head law enforcement official.... do your (insert profane adjective) job!
To use the quality of the video as an excuse to decline to prosecute is pa-the-tic. As others have mentioned above, though eyewitness testimony - by itself - is questionable at best, there is plenty of other circumstantial evidence that can be used to corroborate (and weed out maybe) these witness statements.
It is abundantly clear that this (insert profane noun) is eyeballing a higher position somewhere and doesn't want to risk his (most likely high, based on his lack of any perceivable gonads) conviction rate.
I'm gonna puke just thinking about him.
I get that it wouldn't be easy. For all the reasons (and more) stated above by others. But I would maintain that this case is absolutely winnable - without the video at all. Simply ignore it and use the other evidence.
If the defense wants to introduce the video, let them. Let them make conclusions that you can then pick apart - while standing on the high ground and telling the jury that the video was of such terrible quality that you refused to introduce it so as to not insult their collective intelligence by making conclusions based upon it... and then proceed to show them why you felt you had overwhelming evidence enough without it! I watch a lot of old Perry Mason reruns. (I'm a Raymond Burr fan; I also watch Ironside reruns - not that new, stupid Ironside)
Most everyone who has a 'normal' job can (and probably should) decline to accept work that they deem too difficult. Prosecutors shouldn't have this option.
I so hope the fact that this guy was a professor will come back to bite this gutless (insert profane noun) in the ass and derail his 2016 gubernatorial bid.