We have a problem, i was in a smiliar situation today. The system had 0 defense left but they kept kicking my butt at every fight. 

@Wunderjarl:

This can happen when you haven't improved your roundforce at the same lvl as the enemy (his groundforced are fully upgraded but yours is stock)

@Eldgrim:
Was the population still higher than 1? If so, he could have sacrificed one population so they defend the planet. and when your groundforce from the ships is not large enough you can still loose.

This is strange.

As Eldgrim says it can happen if defender recrurits and if you'r troops are not fully upgraded.

But if you've bought all upgrades for troops...

And looking at your MP deployment limit, even if the defender recrurit a pop unit (it will reach at max the 950 limit, against your >2k)...

Add to this a similar troops/armor/aircraft proportions...

Yes this is weird, and without any more info you should have won.

My fleets had 3k+ manpower each. There was 0 Defense left but their conscript defeated me every time until none was left. That was crazy.

Militarist laws can boost troop damage also some heroes boost system defense. Still results is strange.

Hi,

Could you attach a save ? This way we could try to see if there is a hidden bug or if the values are normal.

This is the savefile Hissho.sav .

@Vind I actually have a militarist govern with those militarist laws you're talking about boosting my already fully upgraded troops, distributed almost equally with 40/30/30%.

Hello!

This is exactly why I'm here. Happened in two separate games: one in an online seassion without any dlcs involved, and the other with dlcs in a single player game. 

nodlcmp.sav  dlcs.sav

For the record, this should now be fixed!