The DUP MP claimed that the Parades Commission is now dancing to a "renegade Republican tune".
"Republicans opened a can of worms in the early 1990s when they instigated objections to traditional Loyal Order celebrations," said Mr Simpson.
"Nowhere has this been more keenly felt than in Portadown where Brendan McKenna has stood for more than a decade against ordinary Protestants walking home from a church service one Sunday a year.
"His intransigence has been one of the primary reasons for failure to resolve this disagreement. Now that he has left Sinn Fein because of their decision to support policing and the justice system he is far beyond their control.
"The Orange Institution in Portadown have made serious and strenuous efforts to resolve this issue, which is more than can be said for Mr. McKenna.
"For years he demanded the Institution accede to his request for dialogue. They have done so in a genuine effort to resolve the problem.
"He ran away from that offer of engagement retreating into an intransigent refusal to compromise. As time goes by his excuses are becoming increasingly feeble.
"What is most despicable about the decision of the Parades Commission determination here is that they have rewarded the actions of a renegade Republican and penalised the genuine efforts of those who are trying to find a way through this problem. What sort of a message does that send out?
"This decision sends out entirely the wrong signal to those who are making determined efforts to resolve this issue.
"As part of the Strategic Review of Parading, the Parades Commission's days are numbered. Decisions such as this show that even in its dying days this hated quango is utterly incapable of dealing with issues surrounding parading in a fair and equitable manner.
"When it's gone it most certainly won't be missed by those of us who believe in fairness and mutual respect."