Who is liable if a homicide occurs because 911 systems were unavailable.

Husband goes to wifes place of employment and begins arguing w her. He was unarmed and the the argument was never physical. There was even a fence seperating the man and women. Unknown to all parties, the local phone system was down, even for 911 calls. The owner of the business sees the 2 arguing and calls 911, but nothing happened due to system failure. Owner becomes nervous thinking maybe the husband cut the phone line and had sinister intentions. The owner, without warning, grabs his .38 and walks right up to the husband and shoots him in the chest. As the husband is bleeding to death, the owner and the wife scramble to contact 911, with no success. The owner eventually gives up on 911 and takes the husband to the hospital, where he was pronounced dead. The phone system was down because a constuction company unintentionaly damaged the phone lines during a project earlier that day. Who would be liable, since he wouldnt have been killed AND might of survived had 911 been available