▁the ▁class ▁of ▁powers ▁that ▁a ▁state ▁could ▁exercise ▁until ▁Congress ▁had ▁acted ▁on ▁the ▁subject . ▁The ▁diss ent ing ▁opinion ▁was ▁intended ▁to ▁also ▁apply ▁to ▁Buck . ▁ ▁Justice ▁McK en na ▁is ▁not ▁listed ▁as ▁particip ating ▁in ▁the ▁decision . ▁ ▁Crit ical ▁response ▁The ▁Supreme ▁Court ▁from ▁ 1 9 2 4 ▁to ▁ 1 9 2 6 ▁issued ▁four ▁dec isions ▁striking ▁down ▁attempts ▁by ▁states ▁to ▁reg ulate ▁or ▁to ▁set ▁tar iff ▁rates ▁or ▁far es ▁of ▁private ▁commercial ▁carri ers ▁that ▁used ▁state ▁high ways . ▁Besides ▁George ▁W . ▁Bush ▁& ▁S ons ▁and ▁Buck , ▁these ▁were ▁Michigan ▁Pub . ▁Util . ▁Comm ' n ▁v . ▁Duke ▁ ▁and ▁F rost ▁& ▁F rost ▁T ruck ing ▁Co . ▁v . ▁Rail road ▁Comm ' n ▁of ▁Cal . ▁In ▁these ▁cases , ▁although ▁presented ▁with ▁the ▁issue ▁of ▁the ▁right ▁to ▁travel ▁in ▁argument ▁in ▁cases ▁such ▁as ▁Buck , ▁the ▁Supreme ▁Court ▁never ▁ruled ▁on ▁whether ▁personal , ▁non com mer cial ▁autom obile ▁travel ▁on ▁state ▁high ways ▁was ▁a ▁constitution al ▁right . ▁ ▁Sub sequ ent ▁develop ments ▁During ▁the ▁Great ▁De pression , ▁which ▁under cut ▁the ▁financial ▁stability ▁of ▁many ▁common ▁car rier ▁companies , ▁there ▁was ▁a ▁concern ▁over ▁the ▁creation ▁of ▁an ▁o vers upp ly ▁of ▁passenger ▁transport ation ▁which ▁would ▁drive ▁many ▁companies ▁out ▁of ▁business . ▁To ▁meet ▁this ▁concern , ▁Congress ▁by ▁the ▁Motor ▁Car rier ▁Act