Many people who voted in the 2018 midterm elections did so at least in part to express their support of, or disdain for, President Donald Trump. Those who don't approve of the president's actions and agenda won out at least in the races for the House of Representatives, where the Democrats now have control. This means that various House committees can now investigate the president in a way that the Republican-controlled House has not yet done. However, now Trump said that if House Democrats investigate him, he has an answer to that — investigating them right back, for something else entirely.
Trump used his most reliable platform to send this message to House Democrats and his base: Twitter. On Wednesday morning, after claiming that "pundits or talking heads that do not give us proper credit for this great Midterm Election" were "FAKE NEWS," Trump turned to Democrats' success in taking back the House:
If the Democrats think they are going to waste Taxpayer Money investigating us at the House level, then we will likewise be forced to consider investigating them for all of the leaks of Classified Information, and much else, at the Senate level. Two can play that game!
Trump does appear to be correct in at least one sense: House Democrats are already preparing to investigate Trump on multiple fronts, according to The Washington Post. Given that the Republican-controlled House has neglected to conduct any oversight on the president or the members of his administration, numerous House committees now have avenues they can begin with, the Post wrote.
California Democratic Rep. Adam Schiff outlined some of what a Democratic House would begin with well before the election, in an October opinion piece for The Washington Post. Schiff, who will now become the House Intelligence Committee Chair, wrote that he would begin by addressing the lingering questions about Trump's ties to Russia, but that would be far from the only high-profile investigation.
Democrats also seem poised to request — and perhaps even subpoena, if necessary — Trump's tax returns, as Vox wrote. The new chairman of the House Ways and Means Committee, Massachusetts Democratic Rep. Richard Neal, told The Wall Street Journal as much in October, and the tax returns certainly haven't come out in the meantime.
The list of investigations that House Democrats will likely begin once new senators are sworn in this January is a long one, as Mother Jones reported. It's far less clear, however, what the Trump organization or the Senate could investigate House Democrats for. The Hill noted that Trump has said he would like to investigate Democratic actions before, either through Attorney General Jeff Sessions' Department of Justice or through Special Counsel Robert Mueller himself.
While Trump mentioned possible investigation topics as "all of the leaks of Classified Information, and much else," that doesn't actually give much information in terms of what the hypothetical investigations would cover. Given the mandate that the Democrats now have — and the questions of possible corruption that have been bothering them and their supporters throughout the Trump administration, as The Atlantic laid out — it seems highly unlikely that they will be pushed into backing down from these investigations because of a Twitter threat.