

Vigilantism is bad because of the slippery slope issue. It starts with solid proof, and then slowly declines towards “vibes”, or fabrication of proof.
“Beyond reasonable doubt” is the high bar set by the legal system, and they have the processes in place to ensure that the bar is met before declaring guilt (its not perfect, but it is so far the best system we have).
If the proof is solid, and the law enforcement is functional, its better to hand it to them and let the system do its job. If the law enforcement isnt functional, vigilantism is all that is left, but you should strive to meet the “beyond reasonable doubt” bar. E.g is the evidence good, do you have the right person, could someone else be framing/manipulating the facts.
You might need to specify the wound placement. I’d change a dressing on a leg or a foot of a colleague or acquaintance, but if its a more sensitive area that might require an actual friend.
Can you go to a medical clinic or ER and get it changed?