Will a car alarm summon help?

Unfortunately, false car alarms are common enough that setting yours off will rarely summon well-meaning neighbors. People are used to curious animals and jostling setting off car alarms, they rarely come running when they hear one.

In an unfortunate 2003 incident, a burglar broke into a Montreal home and the neighbors ignored the home alarm, assuming it was a faulty car alarm. One neighbor admitted, [We all heard the alarm go off but you get desensitized to alarms. I thought it was a car alarm. I said to my daughter `I`m going to close the window because that car alarm is bothering me.`"

If you and your neighbors have agreed that a car alarm is a signal for a home invasion, it might be worthwhile to set yours off–while calling 911. But if you haven`t had these conversations, setting off your car alarm during a home invasion is unlikely to accomplish much.