Does Supralapsarianism make God the Author of Sin?

"If our unrighteousness serves to show the righteousness of God, what shall we say? That God is unrighteous to inflict wrath on us? (I speak in a human way.) By no means! For then how could God judge the world? But if through my lie God’s truth abounds to his glory, why am I still being condemned as a sinner?" (Romans 3:5-7).

A common accusation against supralapsarianism, especially from Arminians, but also even from professing Calvinists, is that it makes God the author of sin. They point out, correctly, that supralapsarianism teaches that God predestined the Fall. Therefore, they say, He forced Adam and Eve to sin. However, that is a false equivalency. Predestination does not imply force, as Calvinists have always said: "Nor is violence offered to the will of the creatures, nor is the liberty or contingency of second causes taken away, but rather established" (Westminster Confession of Faith III:1). Adam and Eve chose to sin. The fact that their choice was consistent with God's decree doesn't change the fact that it represented what they wanted to do. 

Furthermore, the choice of Adam and Eve was to commit an evil act. They knew the commandment of God regarding the tree. They understood that they were disobeying that commandment. And they knew that the desire underlying that choice was to achieve Satan's promise of autonomy from the lordship of God (Genesis 3:5). In every way, what they sought was wickedness. And that was why their choice properly brought them under the judgment of God.

In His decree, however, God had a very different purpose, as Paul describes in the verses above. God's decree of the Fall was certainly not to grant autonomy to Adam and Eve. That would, indeed, have been to seek a sinful end. Rather, the decree was intended to bring about His own glory, the highest good that is possible! That is, God's decree that Adam would fall into wickedness was to the highest good that any end could be.And, therefore, the cavil of the Arminian is refuted.