The reputed gang member accused of gunning down 15-year-old Hadiya Pendleton last month was on the street even though he had been arrested three times in connection with break-ins and trespassing while on probation for a weapons conviction in recent months, the Tribune has learned. In two of those arrests, including one just 2 1/2 months ago, Cook County probation officials failed to notify prosecutors or the judge that Michael Ward had been arrested on the new misdemeanor charges and allegedly violated his probation.