If they were actually aiding the Russia invasion or illegal annexations, it is completely justified to execute them as traitors. Up to 105,000 people who collaborated with the Nazis and Vichy regime in France were summarily executed during and after the Liberation.
EDIT: Note that this doesn't include people who just cooperated with the occupation out of necessity but didn't outright aid it, for example a police officer who continued to serve on the force, or doctors in the hospital, utility workers, etc. In some cases they might face charges depending on the circumstances but execution would be nothing more than murder.
To be honest Russia's level of sheer savagery is closer to the conduct of Japan in the Sino-Japanese war than the German occupation of France so it's even more egregious to collaborate.
The statistic of 105,000 were specifically the ones committed
extrajudicially, as claimed by Adrien Tixier and promoted by an article in the
American Mercury, numbers which have since been dropped down to an approximate 9,000 (or occasionally 30-40,000 depending on the source). Likewise, French sources directly contradict your edit by including victims of the so-called
Épuration who were forced to continue their work out of necessity or to simply survive, victims which include not only the aforementioned doctors, police officers, or utility workers, but notably also women who refused to leave their German husbands they may have married or prostitutes who either continued their work or took up service under occupiers under roles such as maids or seamstresses. It should also be noted that the "purification" of collaborators is to this day a very controversial topic among the French for those reasons stated above and more (including accounts that a portion claims of collaboration were made to extrajudicially handle personal feuds); it is hardly considered "completely justified" and to claim otherwise is a deliberate distortion of the reality and later opinion of the period.
While all that is said, the subsequent
legal trials of collaborators (The accepted manner internationally and by the public), saw about
300,000 claims or cases, of which only 2/5 actually were considered trial-worthy (127,000), and only 1,500 of which saw the death penalty and were executed, the other 97,000 convicted being sentenced to various other punishments such as time-limited "National indignity" (stripping of rights, up to and including seizure of property and expulsion from the country; many accused individuals were tried simply on the grounds of membership to certain parties or groups), permanent indignity, and eventual amnesty post 1951 (for most). This ratio of execution to accused of
0.5%, less than a single percentage point, seems to also be in direct contradiction to the claims of "complete justification", as does the findings of the court to place their comparative number of executions at a mere 1/6th that of the extrajudicial ones using the modern, conservative findings, even more so if using the 105,000 number, which would put it at 1/70th, or about 1.4%.
If anything, the Resistance fighters were the ones considered to be the savages later on by the French, as even Allied sources describe their behavior as akin to that of "a riot, or civil war", acting without the Free French state able to control matters or properly assess their claims due to the war. After all, much like the Revolution, when the town deputy head for the Resistance didn't like the the prices you sold bread at before the war, who would investigate
why someone with such "courage" or "patriotism" accused you of collaboration, lest they be accused themselves?
