Ummmmmmm, why not?
They are his employer, they are entitled to do so.
It is a common practice these days mate, I've got the same thing, if I go out, get sh*tfaced and plow through someones front fence in a car, the company I work for gives me legal representation, they may also be a bit pissed off at me for doing it but that's the way it goes (btw, drink driving sh*ts me and I don't condone it), Stewart might be on a similar wicket.
A co-worker actually did get pissed and plow through a fence, the company gave him the legal firepower necessary, he went from looking down the barrel of long term licence loss, no insurance payout on his car and replacement costs of a large section of fence to basically getting off, no licence loss, barristers etc found protocol had been broken with his toxicology results, insurance paid out, fence paid for, apology from police.
Money talks, bullsh*t walks, Manly know this and will protect their investment.