I have heard the following sentence in the Narcos TV series:
Pues que el muy hijo de puta llenó de policías el Barrio Escobar y se orinó encima de su mural, patrón.
Context: Colonel Carillo, an honest Colombian colonel who is committed to finding and killing Carlos Escobar has recently returned to Colombia after an exile in Spain. His first act after being assigned to lead the Search Block, responsible for capturing Escobar, is going to the neighborhood created by Pablo Escobar and piss on his mural. One of Pablo's hitmen learns about it and tells Pablo the news, using the sentence above.
What is the difference in meaning between orinar and orinarse in this context? In Portuguese, the corresponding verbs "se urinar"/ "se mijar" are only used to refer to accidentally urinating in one's own clothes, e.g. babies, people with urinary incontinence or someone who urinates because of a fit of laughter. Although I think that the Spanish verb "orinarse" is used in the same way, that is obviously not the case in the sentence above.