Jamieson, Fausset and Brown on 1 Kings 2:36

36. the king sent and called for Shimei--He was probably residing at Bahurim, his native place. But, as he was a suspicious character, Solomon condemned him henceforth to live in Jerusalem, on the penalty of death, for going without the gates. He submitted to this confinement for three years, when, violating his oath, he was arrested and put to death by Solomon for perjury, aggravated by his former crime of high treason against David [1Ki 2:42-44].