'I'm OK now. I was gibbering at 8am." It was 1.30pm at a busy cafe outside Westminster magistrates court, and a harried solicitor in her 50s had grabbed a sandwich and a bottle of water to keep her going. She had been working since 2am. She had four clients appearing in court that day, she said, though one had yet to appear before a judge – when he arrived at the court in an armoured van, security guards had been unable to bring him inside as every cell was full.

"Anyone for court six who requires a duty solicitor?" shouted one exhausted-looking lawyer to the throng of defendants, family members, court officials and journalists waiting outside courts five and six, which for three days have been hearing cases related to the riots, almost without a break. "Going once ... going twice ..." Around 80 cases had been heard since the night before, one court usher estimated; official figures, like accurate court lists of those appearing for preliminary hearings, were for the time being, unavailable.

It was a day of similar frenzied activity in magistrates courts across the country, as the long riot cleanup entered its judicial phase. More than 460 people have been charged in London alone in relation to the riots from 1,009 arrests, the Metropolitan police said; nationally more than 1,500 have been arrested. There are certain to be more, however. Scotland Yard detectives are dealing with 550 different crime scenes, of which 140 are still cordoned off; 127 people were arrested in London overnight on Wednesday. Roughly half of those who appeared in court in London were under 18, the Met said.

Thursday saw a relentless conveyer-belt of charges, some of them shocking in their alleged violence and brutality, others strikingly banal. Youssuf Addow, 25, charged with burglary of Phones 4 U in Putney, south-west London, carrying "a mallet, a weight and umbrellas". Peter Morgan, 20, accused of stealing "four cans of spray paint, to the value of £28.92" from B&Q in Hornchurch, Essex. Kaine Thorpe, 24, appearing on a charge of handling stolen goods, "namely Footlocker trainers and a mobile phone".

Again and again, the judges repeated the refrain "jurisdiction is declined". They considered the maximum powers of sentencing available to magistrates – six months in prison, or a £5,000 fine – to be insufficient, and so referred the case to the crown courts, where the cases will be heard before a jury. Very few of the accused were granted bail. At least one solicitor outside court six expressed concern at some of the courts' decisions, on a day when David Cameron had vowed that anyone charged with rioting should be remanded in custody and anyone convicted should expect to go to jail.

Rajinder Claire, who was representing several alleged rioters, said defendants who would normally be released on bail were being routinely remanded in custody. "The decisions seem to be being taken in a routine manner without enough consideration for the distinct factors of each case," he told reporters, "It certainly seems to me that it is being motivated by political pressure."

Certainly there were indications, in the comparatively small number of cases that reached sentencing, that magistrates across the country were in little mood for leniency.

In Manchester, Eoin Flanagan, 18, pleaded guilty to theft after he was arrested in Oxford Road with two jumpers and two pieces of musical equipment; he was jailed for eight months.

At Camberwell Green magistrates, Nicholas Robinson, 23, an electrical engineering student with no previous convictions, was jailed for the maximum permitted six months after pleading guilty to stealing bottles of water worth £3.50 from Lidl in Brixton. He had been walking back from his girlfriend's house in the early hours of Monday morning when he saw the store being looted, his lawyer said, and had taken the opportunity to go in and help himself to a case of water because he was thirsty. He was caught up in the moment, and was ashamed of his actions, his defence said.

But the prosecution told judge Alan Baldwin: "This defendant has contributed through his action to criminal activities to the atmosphere of chaos and sheer lawlessness." There were gasps from the public gallery as his sentence was delivered.

The mother of one convicted looter told the Guardian her son – who got 16 weeks for using "threatening or abusive language or behaviour" – had got a much harsher sentence because of the political climate. "If this wasn't the riot he wouldn't even have got a caution," she said. "It's all because of the riots."

Her son Ricky Gemmell had finished his shift at a Manchester call centre on Tuesday evening and gone home to change out of his suit before heading to the city centre; his family say to visit his girlfriend, with no intention of getting involved in trouble. He pleaded guilty, however, to telling officers during the riot: "I'd smash you if you took your uniform off" before being pinned to the ground and arrested. He became the first rioter to be jailed at a Manchester magistrates court session that began on Wednesday morning and ran late into the night.

At his family home in Gorton, south of the city centre, – a neighbourhood of redbrick terraces where episodes of Shameless were filmed – there was some remorse at his behaviour. But his family's main emotion was dismay at his wasted opportunity, mixed with indignation that, in their view, he had been made an example of. Gemmell had been a prefect at school and was an army cadet. He had applied to join the armed forces earlier this year.

One of twin boys – his brother Ryan is an army cadet – he had left the local secondary school, Cedar Mount High, with six GCSE passes. He had started a vocational public services course – aimed at students planning a career in the uniformed services – at a further education college, but dropped out after a year.

In an area where the male unemployment rate is 11.6%, he had worked in shops, then got a job in a call centre for a digital marketing consultancy. Gemmell had no previous convictions, though he was cautioned for theft two weeks ago.

His mother, who was made redundant earlier this year from a job with the council, said: "You do have a bit of trouble with gangs. He has never been involved with any of it. I've had a copper say to me, he's so chuffed that my lads have never been in trouble. He's not 'known by the police' whatsoever.

"He hasn't hit anyone. He hasn't robbed anything. He was verbally abusive. He knows – you run your mouth, there's a consequence. But the consequence they gave him, it's disgusting."

District judge Khalid Qureshi, however, had not been impressed, calling the riots "some of the worst behaviour this country has ever seen, for no reason whatsoever – and he's part of it".

As day turned to night on Wednesday, a parade of alleged rioters continued to be led into Manchester's courtrooms, among them was a woman who already had 96 previous convictions for theft. Linda Boyd, 31, pleaded guilty to stealing alcohol, cigarettes and mobile phone accessories looted during riots in Manchester. She had found an orange bin liner filled with the stolen goods – "a bagful of loot", in the words of the district judge – in Manchester city centre, the court heard, and had begun dragging it away, intending to share it with friends. She will be sentenced at Manchester crown court on 16 August.

Also appearing was a 17-year-old boy who pleaded guilty to handling stolen goods – two bottles of gin. The boy, a skinny youth with shaved blond hair, was found with the alcohol as he was cycling away from Manchester city centre in the early hours of Wednesday, the prosecution said. His case was adjourned. The judge asked: "Is a parent likely to attend on that occasion?" "We will be in touch," was the best a member of the youth offending team could offer.

Next up was Michael Gillespie Doyle, aged 18, who was accused of entering a Sainsbury's with intent to steal. He mumbled his plea and had to be prompted by the clerk – "is that guilty?" Doyle replied: "Yeah, yeah." His case was adjourned for sentence at crown court.

Back at Westminster magistrates CPS prosecutors, some of whom had already worked two night shifts in a row, were admitting they had never experienced work patterns such as these in their careers. Magistrates have taken have turn to hear cases overnight as the suspected rioters continue to file through the courts.

"Chaos reigns downstairs," a solicitor offered apologetically to district judge Daphne Wickham, as court six waited for the first of 16 defendants to be brought in on a charge of violent disorder in St John's Wood, north-west London, early on Wednesday morning. "It certainly does," she said drily. One by one, the youths, aged between 16 and 21, were brought into the dock, accused of being among a group of up to 50 hooded and masked men who smashed the windows of a cafe, while diners sat outside, some carrying weapons and threatening to set the premises alight with towels soaked in lighter fluid. One diner was robbed of £1,200 in cash.

One of the accused was a 16-year-old youth with eight previous convictions; another, 21-year-old Marouane Rouhi, is a second-year law student, the judge was told, who vehemently denied knowing any of the others or having been involved. Like his co-accused, he was denied bail.

They kept coming, although their stories varied widely. David O'Neill, a 22-year-old chef, lobbed a brick at a police community support officer in Sutton, Surrey. As rioters swept England on Tuesday night, the court heard, O'Neill allegedly had a scarf wrapped around his head and threw a brick at the volunteer officer as he and a colleague approached.

The qualified chef, who had been planning to apply for a loan to set up his own restaurant, did not enter a plea to charges of affray and racially aggravated behaviour causing harassment, alarm or distress. He was one of the few to be released on bail on the condition that he lives at home, wears an electronic tag, observes a curfew, reports daily to his local police station and does not wear a scarf or headgear.

Natasha Reid, a university graduate who plans a career in social work, pleaded guilty to theft after handing herself in to police on Wednesday. Reid, from Enfield, had been in McDonald's on Sunday night when she saw looters ransacking the area and decided to join in. She stole a television worth £269.99 from Comet but, said her defence, had been racked with guilt and unable to sleep since. She was bailed to return for sentencing on 1 September.

Another to hand herself in – although she did not enter a plea – had been a 17-year-old with ambitions to be a dance teacher, who went to police after seeing a photograph of herself looting an electrical shop in Croydon. CCTV caught a group of youths, some masked or wearing hoodies, forcing open the shutters before looting the Richer Sounds shop in Croydon late on 8 August, and allegedly showed her ducking under the broken shutter and going inside before leaving with a flat screen TV in a box. According to prosecutors, she then returned empty-handed a few minutes later and stole another flat screen TV. The store lost £190,000 worth of property and £15,000 worth of damage was done.

Her solicitior told the court she had been doing ballet since she was a young child and wanted to make a career of it. She is estranged from her mother. The televisions have not been found.