Image source, Cheshire Constabulary

This is an exceptionally complex case. Here are the key elements of it:

• Lucy Letby was convicted in two separate trials of murdering seven babies and attempting to kill seven others at the Countess of Chester Hospital between June 2015 and June 2016
• At the end of her first trial, Letby was sentenced to 14 whole-life terms. She was given a fifteenth whole life order in July following a retrial for the attempted murder of Baby K
• The trial ran from October 2022 to August 2023, and the retrial was ordered after a jury was unable to reach a verdict on one count of attempted murder of a baby girl
• The retrial found her guilty of the attacking a new-born infant during a February 2016 night shift at the Countess of Chester hospital
• Letby deliberately injected babies with air, force fed others milk and poisoned two of the infants with insulin
• Dr Stephen Brearey first raised concerns about Letby in October 2015. He said no action was taken and she went on to harm five more babies
• Operation Hummingbird was launched in 2017 by Cheshire Police, and Letby was first arrested at her home in Chester in July 2018
• Two separate applications from Letby toappeal against her convictions have been denied

As a reminder, the Thirlwall Inquiry is not a criminal inquiry – it cannot determine criminal or civil liability, but can highlight where failings have occurred.

We cover many inquiries, and more often than not, they have a livestream.

However, legal representatives of some participants submitted against this being an option.

The chair of the inquiry subsequently ruled that livestreaming will not be allowed. Instead, it’s being held in Liverpool Town Hall, with spaces available for the public and press to attend.

Don’t worry though: you can follow along here for live text coverage from the BBC’s Judith Moritz, who is in the room.

The inquiry has been ongoing since September. Several witnesses have already testified.

Earlier this week, we heard from Letby's former manager, Alison Kelly. She said she "didn't get everything right at the time", but insisted her decisions were made with "the best of intentions”.

Last week, former Det Ch Supt Nigel Wenham told the inquiry that hospital bosses "shut down" concerns from senior doctors that Lucy Letby might be murdering babies on a neonatal unit.

A senior doctor who raised the alarm about Letby said it was “likely” the nurse murdered or assaulted more children before June 2015.

And another doctor previously told the inquiry thatstaff on the neonatal unit felt unable to raise concerns with hospital management, who she described as “detached” and “impersonal”.

You can also catch up on what the inquiry has heard so far by listening to Lucy Letby: The Public Inquiry on BBC Sounds.

Image source, Getty Images

Tony Chambers, who will be giving evidence today, was the chief executive of the Countess of Chester Hospital when Lucy Letby worked there and carried out the murders.

Doctors at the hospital felt their concerns had been ignored by senior hospital bosses at the trust - while Chambers was in the role.

Many have already told the inquiry of instances where they felt their worries were brushed under the rug, and opportunities to report Letby were missed.

He resigned in 2018, after police launched an investigation into the deaths.

Chambers went on to get three senior NHS jobs following the nurse's arrest for murdering babies.

He previously told the BBC: “As chief executive, my focus was on the safety of the baby unit and the wellbeing of patients and staff. I was open and inclusive as I responded to information and guidance.”

Welcome to our live coverage of the public inquiry into the circumstances at the Countess of Chester Hospital, where former neonatal nurse Lucy Letby murdered seven babies.

Today, we’re going to hear testimony from Tony Chambers, the hospital's former chief executive. He is set to be questioned by lawyers for the inquiry today. He'll also face the chair, Lady Justice Thirlwall.

He previously told the BBC that he will “co-operate fully and openly with any post-trial inquiry”.

Our correspondent Judith Moritz will be reporting from the inquiry. Stay with us for key lines and analysis.