Hard to sympathize with anyone willing to endanger innocents...
Seriously, I pretty much stopped caring how wronged/railroaded Jackson's character was the second he decided he was entitled to take hostages and toy with innocent people's lives.
SPOILER
When he pretended to have killed one of the SWAT police officers and threatened to kill more people if Savian didn't kiss his @$$, I pretty much wanted him shot dead on the spot.
In fact, wouldn't in real life SWAT just burst in and take their chances after he supposetly killed a hostage? I mean as far as I know, once the killing starts the hostages are considered to be in imminent danger and thus a violent assault is justified to enter and end the BS right there.
So having him just kill a hostage and threaten to kill more is pretty absurd. If SWAT can get in with a good chance of getting most hostages alive, they would the second a hostage gets killed. I mean, after killing one what's stopping the kidnapper to kill a few more? He's already down for murder 1 anyway.