Well, that's not totally true. What the law says is that if you're upstairs & hear someone in your livingroom, you can't grab your gun & (as the instructors said) go hunting for the bad guy.
The top of the stairs is the "do not cross line".
The top of the stairs is the "do not cross line".
What if its a 1 story house?
"A person who possesses or controls property or has a license or privilege to be in or on it is justified in using reasonable physical force when and to the extent he reasonably believes it to be necessary to stop another from trespassing or attempting to trespass in or upon it. The owner can use deadly physical force only (1) to defend a person as described above, (2) when he reasonably believes it is necessary to prevent the trespasser from attempting to commit arson or any violent crime, or (3) to the extent he reasonably believes it is necessary to stop someone from forcibly entering his home or workplace (and for the sole purpose of stopping the intruder) (CGS § 53a-20)."
Most states now have a "Castle law", which means you do not have to retreat in your own home from an intruder. You can essentially shoot first and ask questions later.
Chasing after an intruder is a different matter. My instructor, and publications by Ayoob and others I have read, agree that a gun should only be displayed if you are directly threatened.
Judging from the newspaper story, I have sympathy for the guy arrested, but I believe he was wrong to give chase and in this case the cops are correct. Strange, however, that the robbers with the backfiring pickup are still at large.