t for lineal relations, collateral kindred
and strangers of the blood, or in increasing the proportionate burden of
the tax progressively as the amount of the benefit increases.[1074] A
tax on life estates where the remainder passes to lineal heirs is valid
despite the exemption of life estates where the remainder passes to
collateral heirs;[1075] there is no arbitrary classification in taxing
the transmission of property to a brother or sister, while exempting
that to a son-in-law or a daughter-in-law.[1076] Vested and contingent
remainders may be treated differently.[1077] The exemption of property
bequeathed to charitable or educational institutions may be limited to
those within the State.[1078] In computing the tax collectible from a
nonresident decedent's property within the State, a State may apply the
pertinent rates to the whole estate wherever located, and take that
proportion thereof which the property within the State bears to the
total; the fact that a greater tax may result than would be assessed on
an equal amount of property if owned by a resident,[1079] does not
invalidate the result.

Motor Vehicle Taxes

In demanding compensation for the use of highways, a State may exempt
certain types of vehicles, according to the purpose for which they are
used, from a mileage tax on carriers.[1080] A State maintenance tax act,
which taxes vehicle property carriers for hire at greater rates than
similar vehicles carrying property not for hire is reasonable, since the
use of roads by one hauling not for hire generally is limited to
transportation of his own property as an incident to his occupation and
is substantially less than that of one engaged in business as a common
carrier.[1081] A property tax on motor vehicles used in operating a
stage line that makes constant and unusual use of the highways may be
measured by gross receipts and be assessed at a higher rate than taxes
on property not so employed.[1082] Common motor carriers of freight
operating over regular routes between fixed termini may be taxed at
higher rates than other carriers, common and private.[1083] A fee for
the privilege of transporting motor vehicles on their own wheels over
the highways of the State for purpose of sale, does not violate the
equal protection clause as applied to cars moving in caravans.[1084] The
exemption from a tax for a permit to bring cars into the State in
caravans of cars moved for sale between zones in the State is n