Yes, it's possible. The post isn't the only thing that's considered- if the poster has a history of rule breaking where they have been previously warned or had posts deleted etc, it is possible that their particular post was the final straw that resulted in the infraction.
On the other hand, if the poster is new to the forum or a regular forumer with no previous warnings or problems in the past, that same post may simply result in it being deleted or likely a warning being handed out.
This is something I complained about when I was Appeals Moderator.
If other misdemeanours are taken into consideration when issuing an infraction, JUSTICE DEMANDS THAT THIS FACT IS DISCLOSED AT THE TIME SO THAT THE APPEALS MODERATOR CAN DO HIS JOB.
As far as I am aware, the infraction reads something like, "Poster X, you have broken rule YY with post #26459, and your penalty is Z". Nothing else.
Only after an appeal or complaint does the mod come back and say "yes, but we took several other posts into account but we can't tell you what they were because they have been deleted."
It's an informal totting up procedure, with no means of discovering what has been totted up and when.
This is basic human rights stuff. No wonder posters are aggrieved by what they see as subjectivity.