A lot of it just comes from what kind of team they were; especially back in the Glory Days of the '70's. You have an owner who looks straight out of Goodfellas, a color scheme of Silver & Black, and a logo of a pirate on it. What else are people going to think of the team? Throw in a reputation for
cheap shot hard-nose playing and a rowdy crew of players made up of people discarded from other teams refuse, and you got the whole outlaw thing going.
And that’s where the fun begins.
The story most associated with the Raiders is the legend that they bugged the visiting team’s locker room. It was so widespread that the then Head Coach of the San Diego Chargers, Harland Svare, scoured the locker room before a game trying to find the damn thing. When he didn't find one, he looked up at the light fixture and yelled, "Damn you, Al Davis! Damn you! I know you are up there." Al's response? "The thing wasn't in the light fixture. I'll tell you that much.'' Yeah, Al was joking. Or was he?
Another coach, Weeb Ewbanks of the Jets, believed that the Raiders flew a helicopter over the Jets’ practice fields to spy on them. And in a great read on CNNSI, longtime football guru Dr. Z recounts how Ewbanks claimed to receive anonymous harassing phone calls during halftime and discovered an Al crony just randomly making himself at home on the Jets bus. The Raiders were also accused of watering down the field before a game if they played a team known for its speed (a trick that happens in baseball all the time).