compel


1 : to cause to do something by the use of physical, moral, or mental pressure : FORCE compelled him to stay in bed>
2 : 1
EXACT, EXTORT <compel obedience>

http://www.wordcentral.com/cgi-bin/student?book=Student&va=compel

After I cheated on the test, and my friend got blamed, I was compelled to confess, so he wouldn’t get in trouble.