If the error is shared in a car collision, the expiation is obligatory

Question: To the noble father, Abdul Aziz ibn Abdullah ibn Baz (may Allah preserve him).
Peace be upon you, and Allah's mercy and blessings:
Q: I was driving a car with four people inside, and I had a collision with another car. One of the people who were with me in the car died during the accident. The deceased's family has forgiven me, knowing that the error was shared between the two cars according to the traffic report.
Do I have to fast two consecutive months in the case of accidental killing? Knowing that I am one of the security personnel, working in the special emergency forces, and the work is very intense, and I am not allowed a leave for two months. We have military training every morning, so I am unable to fast for two months. I ask you to issue a ruling for me, and may Allah preserve you and care for you.

Answer: And upon you be peace and the mercy of Allah and His blessings:
If the error is shared—as you mentioned in the question—then the expiation is obligatory upon you. It is: freeing a believing slave, and if you cannot do so, then fasting two consecutive months, sixty days. The expiation remains a debt upon you until you are able to free a slave or fast.
May Allah make your affairs easy and absolve you of your obligation.
And peace be upon you and the mercy of Allah and His blessings.
Grand Mufti of the Kingdom of Saudi Arabia
And the Head of the Council of Senior Scholars