The likelihood of a criminal investigation and charges against Donald Trump are rising due to allegations by a House panel of a “criminal conspiracy” involving his aggressive drive to overturn the 2020 election results, coupled with a justice department (DoJ) inquiry of a “false electors” scheme Trump loyalists devised to block Joe Biden’s election.

Former federal prosecutors say evidence is mounting of criminal conduct by Trump that may yield charges against the ex- president for obstructing an official proceeding of Congress on 6 January or defrauding the US government, stemming from his weeks-long drive with top allies to thwart Biden’s election by pushing false claims of fraud.

A 2 March court filing by the House January 6 panel implicated Trump in a “criminal conspiracy” to block Congress from certifying Biden’s win, and Trump faces legal threats from justice department investigations under way into a “false electors” ploy, and seditious conspiracy charges filed against Oath Keepers who attacked the Capitol, say department veterans.

The filing by the House panel investigating the 6 January assault on the Capitol by a mob of pro-Trump supporters stated that it has “a good-faith basis for concluding that the president and members of his campaign engaged in a criminal conspiracy to defraud the United States”.

The panel’s hard-hitting findings about Trump’s criminal schemes were contained in a federal court filing involving top Trump lawyer John Eastman, who has fought on attorney client privilege grounds turning over a large cache of documents including emails sought by the committee.

Back in January, the deputy attorney general, Lisa Monaco, also revealed a criminal investigation was being launched into a far reaching scheme in seven states that Biden won which was reportedly overseen by Trump’s ex-lawyer Rudy Giuliani to replace legitimate electors with false ones pledged to Trump.

But the House panel’s blockbuster allegations that Trump broke laws to overturn the election have prompted some ex-prosecutors to call on the justice department to quickly accelerate its investigations to focus on the multiple avenues that Trump used to nullify the election results in tandem with top allies like Giuliani.

“The compelling evidence of criminal activity by Trump revealed by the committee in its recent 61-page court filing should spur DoJ to act expeditiously,” Paul Pelletier, a former acting chief of DoJ’s fraud section, told the Guardian.

“Given the gravity of the revelations, the department should consider a strike force or even a special counsel to coalesce sufficient resources to focus on these criminal attacks that strike at the heart of our democracy,” Pelletier added. “There is no time to waste now that the House committee has provided the clearest view yet into how Trump and his campaign apparently schemed to upend our democracy.”

Other ex-prosecutors say the House panel and the justice department seem poised to increase legal heat on Trump.

“A pincer-movement is emerging in the January 6 investigations of those who conspired to overturn the election,” said Dennis Aftergut, a former federal prosecutor. “The justice department and the House select committee investigating the Capitol siege have turned up the heat on Trump’s inner circle that could ensnare Trump himself.”

Trump and his lawyers have fought unsuccessfully to keep White House records from the panel on executive privilege grounds, and Trump last month sparked strong criticism by calling for massive protests in DC, Atlanta and New York if “vicious” and “racist” prosecutors in those cities probing his political and business activities “do anything illegal”.

Former prosecutors note that the justice department has at least two key criminal investigations under way that could be instrumental in bringing criminal charges against Trump himself.

The criminal inquiry into “false electors” came after referrals by state attorneys general in Michigan and New Mexico where phony slates of electors were assembled with help from the Trump campaign and key loyalists like Giuliani who has also been subpoenaed by the House panel to testify and provide documents.

In addition, the department announced this month it struck a plea deal with one of about a dozen Oath Keepers who had been charged with seditious conspiracy for the attack on Congress on 6 January aimed at disrupting Biden’s certification.

Further in another legal track threatening Trump, a special grand jury in Georgia has been convened by the Fulton county district attorney to investigate Trump’s high-pressure call to the Georgia secretary of state, Brad Raffensperger, on 2 January urging him to “find” 11,780 votes to overturn Biden’s win in the state.

These federal and state investigations could gain momentum given the House panel’s allegations that Trump and his campaign engaged in a criminal conspiracy to block Biden from taking office. Some ex-prosecutors say the panel’s detailed allegations could lead to a criminal referral to the justice department that prosecutors would probably examine seriously.

“The committee’s sworn, evidence-based allegation that former president Trump conspired to overturn the election sends an unmistakable message,” Aftergut said. “The train heading toward a criminal referral to the DoJ is leaving the station.”

Aftergut in a 9 March Washington Post op-ed co written with Harvard Law professor Laurence Tribe called for the attorney general, Merrick Garland, to name a special counsel to lead a Trump related-investigation as the best way to reassure the country that “justice is non-partisan, and fears of political fallout will not determine the decision on whether to bring charges”.

Other former prosecutors say the House panel’s 2 March evidence that Trump broke laws in a criminal conspiracy, coupled with the justice department investigations that are moving forward, could fuel criminal charges against Trump and his top allies.

“The seditious conspiracy charges and the newly announced investigation of fake electors indicate that the government is increasingly investigating more serious and significant charges above and beyond the violent events of the day,” said Paul Rosenzweig, a former federal prosecutor who worked on Ken Starr’s team during the impeachment of Bill Clinton.

“These developments, along with the ongoing investigation of Trump confidants like Rudy Giuliani, suggest that more charges are likely,” Rosenzweig added. “I assume that as part of the ongoing investigation into January 6, the department already has a dedicated task force looking into potential criminal charges against Trump and his top loyalists. If they do not, they should.”

Aftergut said that the House panel had amassed substantial evidence that should benefit prosecutors investigating criminal charges against Trump. “In the course of interviewing more than 600 witnesses, the committee has developed a mountain of evidence that could greatly enhance prosecutors’ efforts,” he said.