A former police officer who argued she had a right to use lethal force when she killed an innocent man after mistakenly entering his apartment has been convicted of murder.

Amber Guyger faces a lengthy prison sentence after a jury found her guilty of the murder of Botham Jean in Dallas on 6 September last year – a verdict Jean family attorneys hailed as a significant moment in the battle to hold police accountable.

Guyger is white. Jean was black.

Standing in a packed hallway outside the courtroom in Dallas, attorney Lee Merritt told reporters the ruling was “a huge victory not only for the family of Botham Jean, but as his mother, Allison, told us a moment ago, this is a victory for black people in America”.

He said: “It is a signal that the tide is going to change here, [that] police officers are going to be held accountable for their actions.”

Merritt said the community should not have had to wait “on pins and needles” for the conviction of someone who killed a man who was “completely non-aggressive, sitting at home eating a bowl of ice cream and someone barged into his home and shot him to death.”

Botham Jean’s mother Allison Jean in court after the verdict was read out. Photograph: Tom Fox/AP

He added: “This should have been automatic, anticipated, expected, but it is extremely rare. From this day forward we are pushing so that it’s not rare.”

The jury began deliberating on Monday afternoon and reached a verdict on Tuesday morning, with sentencing to follow. Guyger pleaded not guilty. In Texas, murder usually carries a sentence of five to 99 years in prison but judge Tammy Kemp had allowed the jury to consider convicting the lesser charge of manslaughter.

Jurors, however, decided that Guyger had committed murder.

Ben Crump, a lawyer for the Jean family, told NBC local news, said: “Thank God, finally America saw the humanity of an unarmed black man who was killed in an unjustifiable way and they returned a verdict that is befitting the criminal, cowardly act of this woman, killing Botham Jean in his own apartment.”

Crump added in a press conference: “This is a precedent now that will go forth across America for equal justice for everybody.”

He said the incident underscores the need for better police training and that the verdict was for “so many unarmed black and brown human beings all across America” who died in interactions with police.

Jean, a 26-year-old accountant, had settled down on his couch to watch television and eat some vanilla ice cream when Guyger entered his home. She claimed she mistakenly believed it was hers and thought he was an intruder.

Kemp controversially allowed the jury to consider whether Guyger’s conduct could be justified under Texas’s so-called “castle doctrine”. Expanded in 2007, it is comparable to “stand your ground” laws in other states and allows a civilian to use deadly force if he or she “reasonably believes … [it] is immediately necessary” in certain circumstances, such as during a burglary.

Though Jean was on his own property and Guyger the intruder, seemingly inverting the intent of the law, her attorneys argued she made a “mistake of fact” when she went to the wrong home, making her subsequent conduct reasonable. They said she was tired after a long day and many other residents had found themselves at the wrong unit in the past because signage was unclear and floors looked similar.

“She made a series of horrible mistakes,” Toby Shook, one of her attorneys, said. “The law recognises that mistakes can be made.”

Prosecutors said it was “absurd” to believe the 31-year-old’s “commando-style” behaviour was reasonable, especially given her training as a police officer and status as a more than four-year veteran of the department.

They noted that Guyger failed to retreat and call for back-up, questioned the veracity of her claim to have given Jean verbal commands before firing, and pointed out that after calling 911 she appeared to provide only limited medical assistance as Jean, who was from St Lucia, lay dying from a chest wound.

Rather than feeling tired, prosecutors alleged, she was distracted because she had been “sexting” a colleague. Jean had a bright red mat in front of his door that ought to have been impossible to miss.

Guyger – who was fired by Dallas police – wept while testifying.

“I was scared this person inside my apartment was going to kill me,” she said. “I ask God for forgiveness and I hate myself every single day. I feel like a piece of crap.”

In closing statements, Jason Fine, a prosecutor, called most of her testimony “garbage”. Fine said Jean did not act in a threatening manner, but started to stand up “like a normal reasonable person who has somebody busting into his home, and before he can even get up he is shot dead in his own home.

“Killing this man was unnecessary and unreasonable from start to finish.”

Special security measures were put in place during the trial. Jean’s death sparked protests and demands for justice from activists who cited it as one of a long line of racially charged shootings by a police department that lacks accountability. Though she was off duty, Guyger was still in uniform and used her service weapon when she encountered Jean.

Critics of the department have also claimed Guyger was given preferential treatment. It emerged during the trial that the head of the Dallas Police Association told another officer to shut off an audio-visual recording system inside a patrol car so that he could have a private conversation with Guyger soon after the shooting.

She still faces a civil lawsuit brought by Jean’s family.

A man is dead after contracting a harmful bacteria from eating oysters on the North Carolina coast, according to family friends.

They say David Argay contracted vibrio in Wilmington, but died Thursday at the hospital.

Argay is from Cary, North Carolina.

Vibrio is a bacteria that lives in saltwater. There are 200 recognized species of marine vibrios but only a few can cause significant problems.

According to the North Carolina Department of Health and Human Services, vibrio infections are associated with eating raw or under-cooked shellfish such as oysters, clams, shrimp and scallops.

The health department did not release details about when exactly Argay ate the oysters or which restaurant served them to him.

Health officials said these types of infections can be prevented by thoroughly cooking seafood or shellfish especially oysters and not exposing open wounds to seawater.

Most infections occur from May through October when water temperatures are warmer.

The CDC reports vibrio causes an estimated 80,000 illnesses and 100 deaths a year in the United States.

Faced with new allegations against President Trump and administration stonewalling, Democrats have ended months of caution.

Speaker Nancy Pelosi announced on Tuesday that the House would begin a formal impeachment inquiry of President Trump, opening a fresh chapter of confrontation in response to startling allegations that the president sought to enlist a foreign power for his own political gain.

“The actions taken to date by the president have seriously violated the Constitution,” she said after emerging from a meeting of House Democrats in the basement of the Capitol. Mr. Trump, she said, “must be held accountable. No one is above the law.”

The announcement was a stunning development that unfolded after months of caution by House Democrats, who have been divided over using the ultimate remedy to address what they have called flagrant misconduct by the president.

In this case, with an avalanche of Democrats — including many who had resisted the move — now demanding it, Ms. Pelosi said that Mr. Trump’s reported actions, and his administration’s refusal to share details about the matter with Congress, have left the House no alternative outside of impeachment. The inquiry has the potential to reshape Mr. Trump’s presidency and to cleave an already divided nation only a year before he plans to stand for re-election.

At issue are allegations that Mr. Trump pressured the president of Ukraine to open a corruption investigation of former Vice President Joseph R. Biden Jr., a leading contender for the Democratic presidential nomination, and his son. The conversation is said to be part of a whistle-blower complaint that the Trump administration has withheld from Congress.

Mr. Trump said on Tuesday that he would authorize the release of a transcript of the conversation, practically daring Democrats to try to find an impeachable offense in a conversation that he has called “perfect.” But Democrats, after months of holding back, demanded the full whistle-blower complaint, even as they pushed toward an expansive impeachment inquiry that could encompass unrelated charges.

“The actions of the Trump presidency revealed dishonorable facts of the president’s betrayal of his oath of office, betrayal of our national security, and betrayal of the integrity of our elections,” Ms. Pelosi said.

In a meeting on Tuesday afternoon, Ms. Pelosi told senior Democrats that the chairmen of the six committees that have been investigating Mr. Trump for various issues would put together their best cases on potentially impeachable offenses by the president and send them to the Judiciary Committee, according to two officials familiar with the conversation. That could potentially lay the groundwork for articles of impeachment based on the findings.

The decision to begin a formal impeachment inquiry does not necessarily mean that the House will ultimately vote to charge Mr. Trump with high crimes and misdemeanors — much less that the Republican-controlled Senate will vote to remove him. But Ms. Pelosi and her leadership would not initiate the process unless they were prepared to reach that outcome.

Ms. Pelosi met privately on Tuesday with the leaders of the six key committees involved in investigations of Mr. Trump, and later huddled with the full Democratic caucus. Her announcement came amid a groundswell in favor of impeachment among Democrats that has intensified since late last week, with lawmakers from every corner of her caucus lining up in favor of using the House’s unique power to charge Mr. Trump if the allegations are proved true, or if his administration continues to stonewall attempts by Congress to investigate them.

More than two-thirds of House Democrats and one Independent have said they now support impeachment proceedings.

The House Judiciary Committee has been conducting its own impeachment investigation focused on the findings of the special counsel, Robert S. Mueller III, as well as allegations that Mr. Trump may be illegally profiting from spending by state and foreign governments and other matters. But that inquiry has never gotten the imprimatur of a full House vote or the full rhetorical backing of the speaker, as Democrats remained divided about the wisdom and political implications of impeaching a president without broader public support.

Now, after the revelation of a conversations between Mr. Trump and President Volodymyr Zelensky of Ukraine in which Mr. Trump pressed the foreign leader to investigate the Bidens, a cascading flood of Democrats has come out in favor of a formal impeachment proceeding.

The shift in outlook among Democratic lawmakers has been rapid, and could yet still turn away from impeachment if exculpatory evidence comes to light. The developments that have turned the tide began less that two weeks ago, when Representative Adam B. Schiff of California, the Intelligence Committee chairman, first revealed the existence of a secret whistle-blower complaint that the intelligence community’s internal watchdog had deemed “urgent” and credible but that the Trump administration had refused to share with Congress.

Democrats have given Joseph Maguire, the acting director of national intelligence, until Thursday to turn over the whistle-blower complaint or risk reprisal. And they have threatened to subpoena the Trump administration for a copy of the transcript of the president’s call with Mr. Zelensky and other relevant documents after Thursday if they are not shared voluntarily.

There were also indications the whistle-blower might not wait around for the complaint to be disclosed. Democrats said on Tuesday that a lawyer for the whistle-blower had informed the committee his client wanted to speak with the House and Senate Intelligence panels, and had requested directions from the office of the director of national intelligence on how to do so.

Tune in as I speak live from the U.S. Capitol. https://t.co/j6UMq4TC5u

— Nancy Pelosi (@SpeakerPelosi) September 24, 2019

Though it has attracted much less fanfare, the Senate Intelligence Committee intends to meet privately with the inspector general and Mr. Maguire later this week to discuss the whistle-blower complaint.