This thread is about one topic: intervening in a bank robbery where the third party is not directly threatened.
Banks have an infinite choice of what they can do to defend against robberies. Some decades ago, banks had bars on the windows, fortified teller cages, and armed guards. For marketing reasons, they decided to abandon those measures and fall back on cameras, silent alarms, and prepared bundles of marked bills that contain dye packs.
Their policy is to offer no resistance, and hope that the robber goes away with his loot.
If someone wants to volunteer to be the armed guard that the bank decided not to hire, that's a personal decision. But he should not expect a medal or even a letter of commendation, nor anyone to pay his medical or funeral bill.
On a practical level, the average bank robber steals about $1000. Sometimes they get as much as $2000. They are usually caught by detective work after half a dozen robberies.
If a defender is shot or stabbed, the ambulance ride and emergency-room bill will be at least $10,000; and the defender could be disabled for the rest of his life.
P.S.: Robbers are not smart (if they were, they would be managing the bank), but they do make rational decisions. If they knew that armed resistance was likely, they would work in teams, lay down covering fire, and take out the armed guards. That is exactly how they worked back in the days of Jessie James.
- Jim