I'm guessing their lawyers have told them not to apologize (show apathy), as it may actually be worse for them in the civil suit.

FYI you wrote apathy when you likely meant empathy.

Apathy fits there if you take the parenthetical to be clarifying "not apologize" instead of just "apologize".

Cops in the US are immune to civil liability for acts while on duty.

There are two flaws in this statement:

1) Police, and most public officials, are subject to qualified, not absolute, immunity.

2) Given that municipal or state governments have to pick up the check when juries find against police departments, the comment you are responding to is still sensible (I'm not saying I agree with it, only that it's not illogical in the matter that you seem to be suggesting).

This comment doesn't need to be downvoted. It's not stating anything as fact - quite the opposite - it's very clear it's just a guess. And it makes logical sense according to this [1]

1. http://en.wikipedia.org/wiki/Non-apology_apology

The officers involved most likely were following both their training and their department's policy here. That something terrible happened as a result doesn't necessarily mean they did something wrong from a legal and professional standpoint. Police work is full of situations that are ugly, even when well-thought out policy is followed to the T.

Of course, the wisdom of ever using flash bangs in policing outside of extraordinary circumstances is suspect.

Which is of course the problem with departmental policy. We routinely see SWAT teams investigating themselves and finding that everything they did was in line with departmental policy.

And policy is not law. We should not allow a shield of false legitimacy protect illegal actions.

The problem is that the law often isn't clear. You have assault, battery, manslaughter, murder, unlawful detainment, and similar laws on the books, all with varying requirements and all with various carveouts for law enforcement, self-defense, etc. They tend to be written in broad language because real life is complicated. In the end, the law in this area is generally in the form of case law created by courts in response to novel situations. The courts have to make judgement calls. In my experience, LE agencies make a lot of effort to ensure their policies conform to existing caselaw and cover the gaps in it. Sometimes they get it wrong. But more often than not, when a policy is particularly egregious, the underlying law is to blame.

In the end, police have broad authority to use reasonable force to effect lawful arrests and searches. And most people don't understand just how broad that authority is under the law.

Which is why the cases in which the police harm or injure people should be brought before the court. Not decided by a prosecutor or grand jury, those entities shouldn't be deciding what is lawful.