Oxford United chairman Ian Lenagan said the club had "thought long and hard about whether to employ a player with his [Luke McCormick's] background."
He added that McCormick's "clear repentance and the opportunity to allow him to rehabilitate whilst meeting our unique goalkeeping situation within the Salary Cap - which we might otherwise not have been able to do - resulted in our decision to sign him".
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The man was fatally injured on the R125 between Swords and Ashbourne.
More than two million men are buried in the region.
After another chilly start for early risers, temperatures will soon climb under the strong June sunshine.