Again, trying to understand the mindset of the period (not my view, mind you), you raised the issue of Masséna's treatment of the Ordenanças. I read Martens on pages 287-288 the following:

"According to modern usage, every individual in a state is not allowed to fall upon the enemy, even after war has been declared against him. Soldiers, by the order of their commanders, and such other subjects as may obtain express permission for the purpose from their sovereign, may lawfully exercise hostilities , and are looked upon by the enemy as lawful enemies; but those, on the contrary, who, not being so authorized, take upon them to attack the enemy, are treated by him as banditti; and even the state to which they belong ought to punish them as such.

If subjects confine themselves to simple defence, it would appear that circumstances ought to determine, whether, acting by the presumed order of their sovereign, they ought to be treated as lawful enemies or not. They are, however, generally treated with more rigour than those who act by express authority."

It would appear - using Martens - that if the Ordenanças only defended themselves the should have expected (based on Martens) to be "generally treated with more rigour" and if they attacked the French, the could be treated as "banditti" unless properly "authorized". The division of Portuguese authority (not sure the proper term) would have allowed - following Martens - the French to claim the Ordenanças acted without authority unless such authority could be proved.

Without applying what I myself may view as "moral" or "right", for the period - again using Martens as a guide - the French treatment could be "in bounds".

While Wellington could try to assert that such authority had been granted the Ordenanças in the end he turned to asking the French for more humane treatment of the Ordenanças. (The "penny dropped" for me in reading the footnote on authority and the reason behind privateers getting "letters of marquze" to avoid being treated as pirates - makes one wonder more about the treatment of our modern pirates at the Horn of Africa.)

See the footnote on page 290 where the "talio" is permitted, but it was a practical manner not to "massacred their prisoners in imitation of the former; but both parties soon found it their interest to desist from these barbarities, and to make war in the usual manner."

As I read this - these are my words in keeping with the times - the English were asking that a higher morale code be used than the "law of nations" (as documented by Martens).

Thus, "barbarous" acts are "in bounds". - R