just last year Democrats sent a letter to Ukraine asking for help to investigate Trump the discussion https://twitter.com/ComfortablySmug/status/1176891061001695233 the letter signed by Senators Menendez, Durbin & Leahy  https://www.foreign.senate.gov/imo/media/doc/5-4-18%20Menendez%20joint%20letter%20to%20General%20Prosecutor%20of%20Ukraine%20on%20Mueller%20investigation.pdf