Okay, here is my question regarding immigration and law?

sec.237a says a c.i.m.t. must be commited w/in 10yrs of gaining LPR to be deportable. i was convicted of c.i.m.t. in 2010 for a crime commited in '96. i gained LPR in '75. to be clear i was "NOT" convicted of aggrevated felony, only c.i.m.t. and it was my only criminal offense, so why was i put into removal proceedings and given the option of voluntary departure if my c.i.m.t. was commited well after the 10yr time limit had expired?also see matter of ALYAZJI , 25 i&N DEC. 397 (BIA 2011) for reference thanks