Why is it so important for danforth to obtain a confession from john proctor, rebecca nurse, or martha corey?

Danforth needed a confession because the rule was that if they did not confess, they were hanged. If they did not confess and Danforth decided not to hang them, the town would become angry because 12 others were already hanged for not confessing.

Hope this helps!

Cause it was important to him now stop being a bully