For the last four years, Turkey’s President Recep Tayyip Erdogan used his relationship with former US president Donald Trump to try to circumvent the US justice system in cases related to Turkish bank Halkbank and lobbying money that went to former national security adviser Mike Flynn, whom Trump pardoned in 2020. But this dynamic is shifting under the Biden administration as investigations related to Ankara resume at both the Justice Department and the Pentagon. Unlike Mr Trump, who routinely called Mr Erdogan from the Oval Office, President Joe Biden has not phoned the Turkish leader yet, even though he has made calls to Iraq, Israel and Saudi Arabia. <a href="https://www.thenationalnews.com/world/europe/turkey-left-shaken-by-us-sanctions-over-s-400-missile-system-1.1129405">Disagreements over Turkish acquisition of the Russian-made S-400 system</a>, congressional sanctions, <a href="https://www.thenationalnews.com/world/europe/greece-blasts-turkey-s-irrational-regional-actions-1.1164548">a more aggressive stance in the eastern Mediterranean</a> and human rights have clouded the relationship. On the judicial front, the Biden administration is pursuing a more assertive role in cases related to Turkey. Last week, <em>Law and Crime</em> reported that the State and Justice Departments had sent an 18-page legal brief to the Washington, DC, circuit court asking it to uphold a ruling that Turkish security agents and bodyguards for Mr Erdogan could be held liable for attacking protesters in 2017. In parallel, the Pentagon's internal watchdog last week concluded its <a href="https://www.thenationalnews.com/world/the-americas/mueller-to-probe-trump-s-former-adviser-over-alleged-rendition-plot-1.674655">investigation into Mr Flynn</a> that had been delayed under the Trump administration. The Pentagon's investigator sent the US Army its findings in the case, which involves Mr Flynn accepting foreign money from Russia and Turkey right before joining the Trump White House. Mr Flynn’s acceptance of these funds could constitute a breach of the constitution’s emoluments clause. Mr Flynn twice pleaded guilty to lying to the Federal Bureau of Investigation but was pardoned by Mr Trump last December. The US Army could serve Mr Flynn with financial penalties for any breach of military rules. But the time frame for such a decision remains unclear. Another case that could see more oversight from the Justice Department under Mr Biden is the Halkbank case currently under way in New York. Turkey’s state-owned bank is charged with embezzlement, conspiracy, money laundering, fraud and helping Iran evade sanctions. Mr Erdogan pleaded with Mr Trump personally to interfere and have the case dropped. <a href="https://www.thenationalnews.com/opinion/comment/john-bolton-s-book-has-no-shockers-but-is-the-writing-on-the-wall-for-donald-trump-1.1036933">According to John Bolton's memoir, <em>The Room Where It Happened</em>,</a> Mr Trump told his Turkish counterpart then he would intervene and dismantle the case. “Trump then told Erdogan he would take care of things, explaining that the Southern District prosecutors were not his people, but were Obama people, a problem that would be fixed when they were replaced by his people,” Mr Bolton writes. Six months prior to leaving office,<a href="https://www.thenationalnews.com/world/the-americas/us-justice-department-removes-lawyer-prosecuting-donald-trump-allies-1.1036230"> Mr Trump removed Geoffrey Berman, the US attorney for the Southern District of New York</a>, but was still unable to dismantle the case. Now, Senate Finance Committee Chair Ron Wyden is urging newly confirmed Attorney General Merrick Garland to look into Mr Trump’s interference on behalf of Turkey in the Halkbank case. In a letter to Mr Garland last Thursday, his first day on the job, Mr Wyden demands answers from the new administration that the Trump team declined to offer. “While the department has failed to co-operate with my investigation, I will continue to seek answers as to why former treasury secretary Steven Mnuchin was directed by former president Trump to improperly intervene in a criminal investigation into the evasion of sanctions in response to a pressure campaign by the Turkish government, and whether [Mr] Mnuchin sought to halt the investigation and prosecution of Halkbank or reduce any fines imposed by the Department of Justice,” he wrote.