In a 'road rage' altercation involving two Muslims, one Muslim was shot dead by the other Muslim and also the murdered man's wife was critically wound

Answer

No, he is not a shaheed. When a Muslim kills a Muslim, both in fact will be assigned to Jahannam. Rasulullah (Sallallahu alayhi wasallam) said:

"When two Muslims confront (each other) with their swords, the qaatil (killer) and the maqtool (the killed one) are in the Fire (of Jahannam)."

Someone asked: 'O Rasulullah! The killer (entering the Fire) is understood. But why the killed one (will also be in the Fire?)." Rasulullah (Sallallahu alayhi wasallam) said: "He also desired to kill his adversary."

Thus both the killer and the killed one are destined for Jahannam. 'Road rage' is pure shaitaaniyat and it is the effect of takabbur (pride). It is utterly disgraceful and lamentable that Muslims can resort to killing each other, and over what? This shaitaani-rage is not a valid excuse for expressing anger.

The one who has erred should swiftly apologize and promise to make amends if his action had caused any damage to the other person's vehicle. If a driver commits a shaitaani act pertaining to driving and ignoring the traffic rules, the other person should suppress his anger, overlook the stupidity of the driver.

If a driver swears or passes crude remarks, suppress the nafs, engage in Thikrullah and ignore the jahaalat of the other person. The Qur'aan Majeed says:

"When they (the Muttaqeen) hear laghw (nonsense/ stupidity/shaitaaniyat), they ignore it, and they say: 'For us are our deeds and for you are your deeds. Salaam on you."