Sixteen conservative lawyers from major U.S. law firms, law schools and think tanks on Thursday asserted their support for an “expeditious” impeachment investigation, arguing in a new public statement that President Donald Trump has abused the office of the presidency.

The letter, published online by the conservative lawyers’ group Checks & Balances, declared based on recent events involving Trump’s efforts to enlist foreign help to investigate political rivals that “the president is abusing the office of the presidency for personal political objectives.”