O’Neill has only been in charge at the Stadium of Light since the start of December, yet already finds himself having to deal with the recent arrests of club captain Lee Cattermole and striker Nicklas Bendtner over allegations of criminal damage.
Both players were released on bail after police questioned them regarding the alleged incident, and the former Aston Villa boss has moved to remind his players of the moral responsibility they have as Premier League footballers.
The former Leicester boss told Sky Sports News: “The police have to finish their inquiries, but it’s a very serious issue and it’s one that wouldn’t be overlooked by the football club.
“We do have some responsibility here. Players and managers, I believe, have extra responsibilities now at football clubs.
“My own view is that behaviour on and off the field is of paramount, decent behaviour.
“The expectation as well, particularly of footballers now in this league, where they are in a very nice position financially, they kind of owe a debt, and that’s something we would like to see happening at this football club.”