Is it permissible in Islamic law to demand blood money from the driver of the car who caused my brother's death, and what is the current amount of this blood money?

The family of the truck driver should have offered condolences and apologized to the family of the deceased.

The truck owner is responsible for the accident because he exceeded the legally stipulated speed limit, and it is most likely that the one who collides from behind is at fault.

The resolution of these matters falls under the jurisdiction of the criminal judiciary or traffic police.

The absence of the truck's lights could be more dangerous than excessive speed.

To determine the amount of blood money (diyah), refer to Fatwa No. 37088.