The City striker is statistically the “dirtiest” player in the Football League after giving away more free-kicks than anyone else in the three divisions.
Hanson has conceded 78 fouls this season – the highest in the league and 15 more than his nearest League One rival, Port Vale’s midfield enforcer Anthony Griffith.
But Parkinson believes the figures are nonsense and the City targetman is being unfairly penalised.
He was unhappy that Saturday’s official Mike Bull frequently punished Hanson when Gillingham often had three men on him.
Parkinson said: “James is the fairest jumper I’ve ever seen. He never jumps with his arms and catches anybody.
“He’s different class at that but he gets too many fouls against him.
“He had (Amine) Linganzi on his toes, the full back right next to him and the centre half marking him. I asked the referee at half-time if he could explain how James could jump any fairer?
“With three players standing on him, what’s he meant to do? It’s absolutely ridiculous.
“But we’ve seen it time and time again. I’m not happy with the (lack of) protection he got, especially in the first half on Saturday.
“It was almost laughable that the ref was giving decisions against him when they were the other way.
"He gave away five free-kicks and there was only one, when he pushed their lad over, which was right. It’s commonsense. With all the people standing on him and pinning him in, at some point James has got to try and move and jump.
“With that movement, there is going to be a bit of contact. The ref then keeps blowing up.” Parkinson contacted Football League referees supremo David Allison earlier in the season, complaining that City’s flair players were not being looked after.
Now he feels that officials should cut Hanson more slack when it comes to aerial challenges.
He added: “We need to have a chat with the refs about that because I’m not happy. Teams do their homework on him.
“The good things from our point of view is that we can identify that on the pitch.
“Gillingham set up with the right back playing very narrow to stop (Rory) McArdle’s angled balls towards Hanson. But in turn that gave Adam Reach more space.
“The right-sided midfield player dropped in deep as well and that gave Adam Drury room to travel and he put some great deliveries in.
“Whatever the opposition do, they are having to think about things to stop us.”