Law modifiers not taking effect

I've got a governor in a settlement who has 2 x +1 law modifiers (aged retainer and Office of Praetor) and 1 x -1 law modifier (popularis)

Yet when he enters the settlement, it has a -1 effect on law in the settlement (from +15 to +10)

There are no other officers in the settlement and I've checked very thoroughly for any other modifiers. I'm not sure if it makes a difference to governing cities, but he also has imperium.

Do the negative law modifiers have a bigger effect than shown? I'm I missing something?
Just when a governor has a net +1 law modifier (and a -1 to unrest modifier as well), I expect him to have a positive effect on order in the settlement.

Searched like hell and couldn't find anything about this on the forums.

They won't have a direct impact on the overall order if there's unrest from other sources there. Which settlement is it? Is there any unrest already present? Could there be enemy spies in the settlement?

But the officer is having a negative impact on order. When he leaves the settlement, the unrest goes down/law goes up. I tried it in a few other settlements and it's the same everywhere with that officer.

It seems like the -1 is overwriting the other modifiers or the others are not being counted somehow. Unless of course there is some particular condition for the positive modifiers to take effect that I'm not aware of (other than having imperium?)

https://i.imgur.com/yFjCHxC.jpg

https://i.imgur.com/Dw5V7jP.jpg

Edit: in this settlement, the unrest ends up the same because the extra garrison from the officer was enough to compensate for the decrease in law, but where I already have full garrisons, I was hoping to use this guy to bump up stability.

What are his traits and ancillaries? If he's not having an impact, it's likely because the combination of them is negative.

I said in the first post, 2 x +1 law modifiers (aged retainer and Office of Praetor) and 1 x -1 law modifier (popularis)

I've checked very thoroughly, these are the only modifiers that affect law.