'Start Here': London reeling after stabbing attack and White House won't participate in House Judiciary impeachment hearing

Here's what you need to know to start your day.

It's Monday, Dec. 2, 2019. Let's start here.

1. London terror

Police in London say the suspect accused of killing two and injuring three others in a stabbing attack near London Bridge on Friday was a convicted terrorist who was released in 2018.

Police shot and killed Usman Khan after bystanders subdued him using a fire extinguisher and a narwhal tusk from a nearby bar.

ABC News Senior Foreign correspondent Ian Pannell explains that many are calling for a change to the law that allowed Khan to be released early: "The reality will still be the legal system as it currently stands means people will be allowed out at some point. You can't lock people up indefinitely."

2. Can I get a witness?

"As for the hearing scheduled for December 4, we cannot fairly be expected to participate in a hearing while the witnesses are yet to be named and while it remains unclear whether the Judiciary Committee will afford the President a fair process through additional hearings. More importantly, an invitation to an academic discussion with law professors does not begin to provide the President with any semblance of a fair process. Accordingly, under the current circumstances, we do not intend to participate in your Wednesday hearing," White House counsel Pat Cipollone wrote in a Sunday evening letter to Chairman Jerry Nadler.

ABC News' Katherine Faulders tells "Start Here" that House Republicans continue to back up the White House in this debate: "They've accused Democrats of blocking their due process rights. Well, they won't be showing up for this on Wednesday."

3. Trump's Afghanistan surprise

During his first visit to Afghanistan, Trump announced on Thanksgiving that peace talks with the Taliban had been reignited.

ABC News' Elizabeth McLaughlin explains to "Start Here" that the Taliban’s refusal to talk to the Afghan government remains a big sticking point.

"Start Here," ABC News' flagship podcast, offers a straightforward look at the day's top stories in 20 minutes. Listen for free every weekday on Apple Podcasts, Google Podcasts, iHeartRadio, Spotify, Stitcher, TuneIn or the ABC News app. Follow @StartHereABC on Twitter, Facebook and Instagram for exclusive content and show updates.

Elsewhere:

Murder suspects on the run: Four teenagers, including two charged with murder, fled from a juvenile detention center in Nashville late Saturday.

'Indescribable violence and homicides': Authorities in Mexico announced the arrest of "several individuals" related to the massacre of nine U.S. citizens by drug cartels last month.

64-year anniversary: Montgomery, Alabama, unveiled a statue in honor of civil rights icon Rosa Parks, whose 1965 bus protest integrated public transit and played a role in the national Civil Rights Act.

'It's a good idea': John Sinclair, the activist and poet who spent almost three years in jail from 1969 to 1971 for possession of two joints, was first in line to buy legal weed on Sunday as Michigan became the ninth state to sell recreational marijuana.

From our friends at FiveThirtyEight:

2019 NFL Playoff Predictions: Once Monday Night Football wraps, there will be only four games left for every team in the NFL. Take a look at where FiveThirtyEight's playoff predictor thinks teams will end up with 25% of the season left.

Doff your cap:

Pop stars often get plenty of bad press, but Sia proved over the holiday weekend that she's no diva.

The "Chandelier" singer, who's not even from the U.S., nonetheless was in the Thanksgiving spirit as she picked up the check for everyone at the registers at a Walmart in Palm Springs, California, on the holiday.

Of course, most of the shoppers had no idea who she was at first since she famously covers her face during performances.