NASHVILLE, Tenn. (WTVF) — How do the dates on an email magically change - or spaces suddenly appear?

Those questions are at the center of the continuing controversy over whether House Speaker Glen Casada's office may have tried to frame a student activist who had become a thorn in the Speaker's side.

Now, the legislature's Black Caucus wants the TBI to investigate.

The controversy focuses on a screenshot that Casada's now-former chief of staff, Cade Cothren, sent to Nashville's DA back in March in an apparent effort to get activist Justin Jones locked up.

Cothren's email suggested that student activist Justin Jones may have violated a court order to have no contact with the Speaker just a day after an incident on February 28th. In that case, a cup was thrown onto Casada's elevator and Jones was arrested.

Cothren sent the DA a picture of an email from Jones that was dated March 1st.

But the activist's email had actually been sent on February 25th -- three days before his arrest.

"TBI needs to conduct an independent - an independent - investigation of all of these matters related to that email," said Rep. G.A. Hardaway, a Memphis Democrat who chairs the Black Caucus.

Hardaway said his members are not content with Casada's explanation of a computer glitch.

After our story first aired, the Speaker's Office released Cothren's first email to the DA's office in which the real date does appear.

The chief of staff later sent the pic to the DA with the bogus date. Casada's office says that's the date the email was actually delivered.

But take a closer look.

In the real email, the date appears on the second line.

But in Cothren's pic, the bogus date appears under the email addresses.

"The screenshot of the email truncated the email so that the only date showing was the false date," Hardaway said. "I have an issue with that."

Cothren had claimed that the date somehow changed automatically when he tried to forward it to the DA's office.

But, again, look closely.

The email was also copied to an address at "tennessean.com."

But in Cothren's pic provided to the DA's office, a space suddenly appears in the middle of the email address.

Was it altered?

Statements provided by the Speaker's office have not explained those discrepancies.

"There are several issues that need to be addressed here in terms of the civil rights, in terms of the criminal action, with the email," Hardaway said.

These questions come a day after Cothren's resignation and as the House Speaker continues to deal with the controversy over his former chief of staff's text messages.

Included was a 2016 text message where Cothren said "black people are idiots," another where he he used the n-word and an exchange with Casada where he used a "black people" meme apparently in reference to a West Tennessee district.

"I think if the Speaker of the House had come out last week and said that 'I'm sorry that these words were used' and made a genuine apology, I think that would have been a good first step," said Sen. Brenda Gilmore, D-Nashville. "Certainly not the end, but that would have been a good first step."

Her Nashville colleague, Rep. Vincent Dixie, said that's not what he wants.

"An apology is not enough," Vincent said. "I don't want to hear 'I'm sorry. I didn't mean to do that. I want measured steps. I want action taken. I don't want any more words - none.

Dixie complained that the racist texts did not bring calls for Cothren's resignation, that it took vulgar texts about "white women," as he put it, to bring about calls for change.

That, these lawmakers argued, says something.

"We want to change that deep state of bigotry, that deep state of mysogynism that exist up here on Capitol Hill," Hardaway said. "That's where the Black Caucus is going, and we won't stop until we get there."

A TBI spokesperson said the agency is aware of the Black Caucus' request for an investigation.

Nashville DA Glenn Funk has asked the state DA's conference to appoint a special prosecutor, and the TBI said it will be working with that agency to figure out its next move.

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