Five days into his trial at the Old Bailey in May 2013, Hazell changed his plea from not guilty to guilty. He was sentenced to life imprisonment with the judge setting a minimum term of 38 years.
Hazell told police that Sharp had left the house on 3 August 2012 to travel to Croydon, five miles away, to buy shoes in the Whitgift Centre.
On 7 August, Sharp's uncle, David Sharp, made a televised plea for her safe return. Fifty-five sightings were reported by members of the public, but none was substantiated. Eighty police officers were assigned to the search, and 800 hours of CCTV footage were collected. On 9 August, Hazell appeared on an interview for ITV News, denying that he had done anything to Sharp and praying for her safe return.
On 10 August, a body was discovered in a black bed sheet in a black bag in the loft of the home of Sharp's grandmother, after police visited it for the fourth time. Police launched a search for Hazell, and arrested him on suspicion of murder that evening at 8:25pm at Cannon Hill Common, Morden, after a tip-off from a member of the public. It was later announced that two further arrests had been made: Sharp's grandmother, Christine Sharp, on suspicion of murder, and Christine's neighbour, Paul Meehan, on suspicion of assisting an offender. Christine and Meehan were subsequently bailed. Commander Neil Basu, the officer in charge of the investigation, apologised to Tia Sharp's mother for the delay in finding her daughter's body. He blamed human error and said that a review would be undertaken "to ensure such a failing is not repeated".
In the early hours of 12 August, Hazell was charged with the murder of Sharp. He appeared before Camberwell Green magistrates' court on 13 August via video-link. No plea was entered and the case was committed to the Old Bailey for trial, with a first appearance on 15 August, also via video-link, with a preliminary hearing set for 19 November and a provisional trial date set for 21 January 2013. He was remanded in custody to Belmarsh prison where he was kept in isolation for his own safety.
A post-mortem on the body began on 10 August, and paused later that day. By 16 August, the post-mortem had still not been completed, but at an inquest into the death, which opened that day, it was confirmed that the body was that of Tia Sharp. The post-mortem later concluded without establishing the cause of death. Experts told This is Croydon Today that the delay in finding the body made it much harder to establish the cause of death, and that without a cause of death the prosecution would find it much harder to build a case. However, detectives suspected, and it was widely reported, that Tia Sharp was smothered, although this was not officially proven to be the cause of death.
On 23 August police commissioner Bernard Hogan-Howe addressed his force's failure to find Sharp's body. He said the error could not be attributed to a single officer, and that he wanted to "understand what processes and management decisions we've made that led to that failure."
Tia Sharp was cremated on 14 September, after a private family funeral.
It was announced on 26 November 2012 that Hazell would face trial in May 2013.
On 7 December, the Metropolitan Police announced that Christine Sharp would not face charges.
On 5 February 2013, neighbour Paul Meehan was charged with wasting police time. He appeared at Croydon magistrates' court on 28 February 2013, where he denied the charge against him and was released on bail for a one-day trial on 29 July.
Hazell pleaded not guilty to murder when he appeared in court on 8 March 2013.
The trial of Hazell began on 7 May 2013 before Mr Justice Nicol. On 13 May, Hazell changed his plea to guilty and was sentenced to life imprisonment on 14 May with a minimum term of 38 years, meaning he will be 75 years old before he is eligible for parole.
On 5 August 2013, Meehan was found guilty of wasting police time and sentenced to five months in prison.
In June 2013, Sharp's biological father, Steven Carter, announced that he was going to be a father again, as his girlfriend was pregnant. In July 2013, Carter said he backed a plan for websites to be told to block certain search terms and warn people when they try to view illegal content.
In June 2013, the home of Christine Sharp and Stuart Hazell, where Tia Sharp was murdered, was demolished and in mid-2014, work began on new houses being built on the site.
In November 2013, partly in response to the murders of Tia Sharp and April Jones, the search engines Google and Bing modified their systems to block results from searches aimed at producing child abuse images.
In March 2014, the murder of Tia Sharp was featured in CI Channel's series, Britain's Darkest Taboos, as the first episode of Series 3, broadcast on 16 March 2014.