Their crime is one of perverting the course of justice - something that has to treated with a harsh sentence to shore-up the foundations of the judicial system. It matters not whether it was to avoid a speeding fine or to get out of an attempted murder conviction. What's more he was a pillar of the community and, therefore, has to be treated in a fashion that recognises his hypocrisy and arrogance.
As for the paedophile scout master, I know nothing of it bar what you write, but of course nothing short of a long prison sentence should be handed down for his crime on the face of it. He was in a position of trust and his betrayal of that is more heinous than a man in the street's commission of the very same offence. Even the 'ordinary' member of the public who assaults a child should be imprisoned. The suspension of a custodial sentence for this is a miscarriage of justice in my view.