1 Kings 2:41 (ESV)

41 And when Solomon was told that Shimei had gone from Jerusalem to Gath and returned,

If Shimei believed Solomon no longer cared about him and his whereabouts, he was mistaken. If he thought his journey had gone unnoticed or unreported, he was equally mistaken. Solomon was told about Shimei, and he sent to have him brought to him. This summons was not for the purpose of a casual conversation. Shimei was brought before Solomon as his judge. We are to imagine a judicial case.