canada
The acts of the driver that you describe would constitute several different Criminal Code offences.
The availability of self defence as an an excuse or justification for those offences depends on whether the statutory elements of the defence are made out. These are codified at s. 34 of the Criminal Code:
34 (1) A person is not guilty of an offence if
(a) they believe on reasonable grounds that force is being used against them or another person or that a threat of force is being made against them or another person;
(b) the act that constitutes the offence is committed for the purpose of defending or protecting themselves or the other person from that use or threat of force; and
(c) the act committed is reasonable in the circumstances.
(2) In determining whether the act committed is reasonable in the
circumstances, the court shall consider the relevant circumstances of
the person, the other parties and the act, including, but not limited
to, the following factors:
(a) the nature of the force or threat;
(b) the extent to which the use of force was imminent and whether
there were other means available to respond to the potential use of
force;
(c) the person’s role in the incident;
(d) whether any party to the incident used or threatened to use a
weapon;
(e) the size, age, gender and physical capabilities of the parties to
the incident;
(f) the nature, duration and history of any relationship between the
parties to the incident, including any prior use or threat of force
and the nature of that force or threat;
(f.1) any history of interaction or communication between the parties
to the incident;
(g) the nature and proportionality of the person’s response to the use
or threat of force; and
(h) whether the act committed was in response to a use or threat of
force that the person knew was lawful.
To summarize:
- the driver must have held a subjective belief in the use of force against them;
- that belief must have been objectively reasonable in the circumstances;
- the acts/offences sought to be excused or justified need to have been taken with the subjective purpose of defending themself against the use of force; and
- the acts/offences sought to be excused or justified need to be reasonable in the circumstances
Without much more detail, I am not even a position to answer how I would conclude those issues, let alone predict how a properly instructed jury would. But, I predict that the main issue will be factors 34(2)(b) (alternative responses) and 34(2)(g) (the nature and proportionality of the response).