While Mars has potential for having such a high salinity, that doesn't completely rule out life. There
are organisms that can strive, and some
that even depend, on high concentrations of salt.
For example, the algae Dunaliella salina lives in fresh waters but can also be found in the Dead Sea. On top of that, proteins called halophilic
proteins actually depend on high concentrations of salt to form. Granted, a protein isn't an actual living organism, but it's progress in the right
direction.
Source - Astrobio.net 
I would say yes of the Mars we see today but oceans affect weather and who knows what it was like back when mars had large amounts of
surface water but being too salty kind makes since like Salt Lake, or the Dead Sea where slowly the ocean water is evaporated away and you end up with
things like the Salt Flat etc. 
