Sir, – After the M9 crash in Co Kildare, which left five teenagers dead and four people seriously injured, we need to consider every possible way of stopping dangerous vehicles before they reach innocent motorists. One technology worth examining is the Grappler Police Bumper, already used by police in the United States. It deploys a strong webbing from a patrol car that catches the fleeing vehicle’s rear wheel or axle, allowing it to be slowed and stopped.It sounds like something from James Bond, but it is real and already in use.Given the dangers of wrong-way driving and high-speed pursuits, could this be something the Garda should trial on Irish motorways?It may be worth pursuing. – Yours, etc,NUALA HAYDEN LEONG, Brentwood, US.