All it takes is a desire to find the truth, something you avoid to send people to Mars on a suicide mission. You don't care about the possible benefits of finding life on Mars and what it could mean for the study of life on our planet, all you care about is sending people to Mars tso you can say "we did it." How vain can you get?

Here is Dr. Benton Clark's (far more of an expert than I) on the subject you address:

MARTIAN METEORITES DO NOT ELIMINATE THE NEED FOR
BACK CONTAMINATION PRECAUTIONS ON SAMPLE RETURN
MISSIONS
Benton C. Clark

From: Adv. Space Res. Vol. 30, No. 6, pp. 1593-1600, 2002

MARTIAN METEORITES

What hhs been called the "rain" of martian meteorites can hardly be called a flood. To date, only 0.1% of the tens of thousands of meteorite specimens are identified as of martian origin. This is undoubtedly too low for estimating the natural frequency of infall because of the bias against identification. Iron
meteorites are most common in collections, because they are the most bizarre and easiest to recognize as different from typical terrestrial rocks. From the relative frequencies found in Antarctic and desert-plains meteorites, where few natural terrestrial rocks are present, the lunar and martian meteorites undoubtedly
comprise a greater percentage of the infall. None of the martian meteorites discovered to date are "fresh." All have been in space for between about
500 thousand and 20 million years as revealed by their cosmic ray exposure ages. The same rough scale of antiquity holds even for a portion of the meteorites coming from our much nearer neighbor, the moon. If martian organisms did arrive "recently", most of them took millions of years to get here. Except for the
case of organisms buried deep inside large boulders, it is clear that in such transfers, all organisms would be exterminated by the lethal space environment. In a separate paper (Clark, 2001), the numerous barriers to successful transfer of viable biological materials have been already delineated, with emphasis on certain
of the pertinent factors, such as the in-space radiation sterilization of samples and the improbability of launch of materials which are most likely to be biologically-inhabited (e.g., sediments, aqueous materials, etc.). It is often pointed out that a small but important fraction of meteorites could arrive here much, much
faster (Gladman, 1997; Mileikowsky et al., 2000) and hence survive the multiple threats of ionizing radiation, vacuum inactivation or thermal stress."

THE CHAOTIC HISTORY OF LIFE ON EARTH

"In numerous recent comments, the point of view has been expressed that "we have survived martian meteorites, so they cannot be hazardous." This flies in the face of the enormous upheavals in the terrestrial biosphere, the ebbs and flows, as well as the millions of extinctions of species that is obvious from the documented paleontological record. Life on Earth has been anything but blissfully static. Species, Genera, even whole Orders, come and go. Climate change and biological competition are undoubtedly prime movers in a large fraction of cases, but the fabric of evidence is far too threadbare to determine the culprit in all but a few favorable situations. Neither the proximate, penultimate, nor ultimate causes can be rooted out. How are we to be sure that one or more of the plethora of known cases of extinction or decline was not caused by biological invasion or infection from an "alien" organism? Of course, "alien" can be simply something, or someone, from over the mountain, or across the river, rather than ET from the heavens."