For anyone who has had a client in criminal court facing potential deportation, they may be familiar with Padilla v. Kentucky. The full Supreme Court decision for Padilla is available here. The Supreme Court clarified the confines of ineffective assistance of counsel when applied to a criminal defendant assenting to a guilty plea without knowing the risk that the guilty plea could have on their citizen or non-citizenship status.
In Commonwealth v. Clarke, the Supreme Judicial Court held that Padilla should be applied retroactively. The case decision is available here. I cannot summarize the impact of the Padilla decision and the Padilla elements in two paragraphs. Nor can I explain the intricacies of the Clarke case in relation to Padilla in two paragraphs. But, I can refer you to a helpful article, available here, that was published in the Boston Bar Journal written by Jesse Boodoo that expands on the two cases.